I am the proud owner of a 406 D9 Break HDi 110 from 1999, I am going to introduce myself and give a little background about my car so this text might get long (sorry), if you want to skip it but still try to help, which I totally understand, you can scroll down to the end of the post which is where I'm going to place some minor questions.
So, I'm from Lisbon-Portugal and drove a Renault Clio until 2 years ago (when I gave it to my sister), since then I've been driving this lovely car and will keep driving it for a couple more years.
My father bought it new, I don't know the Trim of it but it has heated & electric leather seats, leather steering-wheel, a/c, woodish trims on the Dash and Doors, Cassete Radio & Cd-changer on the back, automatic windscreen wipers, headlight washers...and I guess that's it, doesn't have Cruise-Control.
It all went great for 4 years but then, due to a very unfortunate event, he wasn't able to pay the parcels to the bank...to avoid the bank from "snatching" the car from him, he "loaned" the car to a "friend" and the "friend" paid for half the parcel (all my father could afford during that year)...This is where everything collapsed, his "friend" (and group of gipsy friends) totally ruined the car, completelly trashed (leather steering-wheel and seats were scratched and ripped apart, "garbage" everywhere, parts missing from the interior, parts broken on the exterior...you name it, and it probably happened), the only positive thing that we eventually found was that about 90% of the mileage they covered were made on the Highway on very (very) large trips across Europe to Romania.
2 years ago, he gave me the car because he almost never drove it and loved the gesture of me giving my Clio to my sister, so I took it with open arms (some things were already replaced/repaired so it was good enough to drive proudly(ish))
Right now my pug marks 292,000 miles, which is a lot, but this engine is a monster and refuses to give up. In these 2 years I spent around 2,500 Pounds with it (comments on this after...), not really because I wanted, but because when my mechanic friend placed the car on the elevator, he was completely amazed that the car was still running without burning up (oil EVERYWHERE coming out of EVERYWHERE)...He replaced a few parts, oil kept coming out from other places, he kept replacing untill there was no visible leak, however, small amounts of oil kept leaking.
For me, the car was running good (hell, I never drove it before and compared to my old Clio it was much better so, how on earth would I know?) but my friend took the car for a spin and noticed that it was lacking a lot of power, he took the Turbo out, and again, he couldn't figure how the car didn't blow up. The turbo was sucking oil and fuel and it was about to break.
And this kept going, and going, and going, small repairs, major repairs, in the end we can say that pretty much all the parts were either replaced or repaired (Turbo, Campbelt, EGR, Valves, MAF, Tubes, Rubbers, even the bloody tip of the exhaust fell when I was driving, etc...again, you name it and I probably have the bill for it somewhere), the only thing left untouched was the engine itself (I don't know the mechanical terms, but I suppose it's the Engine Block, Cylinders, etc).
This was a friend that has an Autoshop, if it was done in a normal Autoshop, I can't imagine how much it would have cost.
And now you ask, "why spend more on the car than what the car itlsef is worth?" well, first: because my friend would let me pay in parcels whenever I was tight on cash (pretty much always...), second: because to buy a car as good as this one I would need to spend way more and wouldn't know if the car would need repairs or not, third: Because 3 different mechanics praised my car engine, dispite all the troubles with the Individual parts, they said (and say) that the Engine is running super smooth and perfectly tuned, in better shape than most 60k mile cars that appear in their shops
and finally: because I LOVE THIS BLOODY CAR 
There are still some things that need to be fixed but I'm taking care of them slowly and doing what I can by myself. A/C has a leak somewhere, so this Summer is not going to be very nice
, I can't find the stupid rubber that sits between the rooftop and the rear door (water doesn't get into the car...yet...), lots of scratches in the paint, sterring wheel and seats are being slowly repaired and dyed by myself, some punk stole one of my Rims center Cap 
oh well, small things that time and cash can repair (I've been reading this forum for 2 months now, you guys Rock and have helped me a lot, thanks for that).Having said that, until yesterday, the car was running perfectly fine, today the Clutch Started to Slip, which is not a major problem for now but means that I'm already preparing myself to pay for a Clutch Kit & and Flywhell...And this leads me to my first question
I saw this LuK kit with the reference 600 0048 00 (ex: http://www.yoyopart.com/oem/7200769/luk-600004800.html) and all the bloody sellers that I have contacted can't tell me if it fits my car or not, because they only have the OEM ref for the complete Kit and Peugeot never had an OEM for all the parts together (only for the Clutch Kit and Flywheel sepparately)...Can any of you experts advise me on this? (car complete details at the end of the post)
Second Question: Since I'm changing the Clutch and most expensive parts are almost new, I was thinking about remapping my engine in a local specialized shop that works mostly with Peugeots and Renautls, the guy told me that the car would get between 132-140 bhp but only after running it on the test bench he would know for sure what's the best setup without forcing the car too much (I liked these guys, professional and seem to care about the cars...they were also recommended by my mechanic).
What do you guys think, good idea? Do you recommend any changes together with the remap?
Thank you very much for reading this and helping, I will post some pictures when I get the chance (maybe this weekend) and for sure will be an active user here in the forum.
Car Details:
Peugeot 406 Break (08.1999)
2.0 HDI 110
VIN: VF38ERHZE80905773
I'm doing an average of around 50-55mpg after changing the MAF and with a slipping clutch, so I guess I can do even better when the clutch is fixed 
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