Took the front end apart on my 71 and found the core support is in ok shape but looks like it should be replaced my question is most websites that sell after market repros say fits 70-72 after earlier discussions i want to be sure that im not going to have any issues with fender or hood fitment .

https://classicbodyparts.com/product...RoCgXgQAvD_BwE

 

As I recall, they all say that the '70 fits '71-'72 "with modification".

I think they all come from Dynacorn, so you might contact their sales or support, or Classic Body Parts', to see what is required. Or someone here will reply.

FWIW, shipping on these is outrageous, and they are often unavailable from any supplier. I have one that arrived too late for my project, still new in the box. I haven't gotten around to listing it in the parts-for-sale here yet. If you are close enough to pick it up, it might make sense for you. I'm in the southeast US.

 

The center support is different for the 70, basically right where the hood latch portion is, I believe with the reproduction it should unbolt and you can bolt your center support from your current core support in its place as long as it’s in good shape still.

 

The '70 core support is VERY different than 71-72. All of the aftermarket reproductions are the '70 design. The top plate is entirely different. I'm not sure what 'modifications' they have in mind, but it would be pretty extensive.

You're better off finding a better original core support - they're still out there - or repairing yours. You might be able to use pieces of the repop as patches. I ended up stitching together two core supports to get one good one.
You can use a 71 or a 72 - the 72 grills curved back and went under the top plate, so there are bumps in the top plate to clear the grille. The 71 grills are straight, so the top plate is flat. So 71 grills fit a 72 core, but 72 grills do not fit a 71 core.

 

Note that all three years (1970. 71, and 72 are different core supports. You can use a 72 on a 1971 car but it will not be optically correct. A 71 core support will fit a 72 if you are using 442 grills but not with Cutlass or Supreme grills (but aren't they all Faux Four Twos now?).