Scott
Here's a picture of the front fender welt on an un-restored '49 GMC
'49 and my '52 GMC I recently completed.
'52 I am very happy with the way it turned out. As you are probably aware the welting was only used on the front fenders presumably as both an anti-squeak and to keep debris from building up in the fender to cowl joint. The front end of the welt is tucked between the filler plate and front fender.
welt The welting I used was very much like the original with the bead sewed to a cloth like material. Unfortunately I got this material with some other used parts I purchsed and don't know where it came from originally.