Radiator Core support Q

[Ackattack]

I'm working on building the 68, and looking over the parts I'm going to be needing in the future. I'm going to go with a GMC grill. However the core support for the 68 is a little different than the one in my 72 GMC. Mainly, the 72 GMC's has extra pieces behind the head lights.

Can I use a chevy core support with the GMC grill or do I need to get that extra piece to support the headlights?

I guess if all else fails, I can go look at the GMC's grill and see if its needed, but it's easier if someone here knows.