Hi John
I think every case is a little different depending on how much replacement or
re-pop sheet metal is used in putting the truck back together.
In my case (51 panel), I have all Chinese fenders & grille attached to the original stock radiator support and stock inner fenders (stock hood too).
I have put it all back together VERY carefully after painting ( did not fully attach
the front clip stuff before paint due to a scheduling issue, big mistake)
THe grille will not align properly with the core support or the inner fenders; and the fenders will not align with the grille.
Although I got it all "close" I am about to take it all apart, drill BIG holes in all the Chinese stuff and assemble it all off the truck; then attach the whole front clip
as the shop manual suggests.
It is a pain to try to attach the fenders one at a time; esp, after paint.
squire