I managed to crack the rear bumper on our green 2000 Exec.

I have read of bumpers being welded with a soldering iron, using some material pared from somewhere on the bumper where it won't show as the "welding rod". Would mean removing the bumper first to get at the cracked bit. Sounds a bit of a kerfuffle, and the bumper is functional, so I'm tempted to leave it until I can find a replacement bumper from a scrappy unless it is fairly straightforward to do the welding bit and likely to produce a good repair.
Any suggestions please?
Regards,
Simon