is there a difference between a 66 frame and a 67 frame both are 2 door hardtop. also is there a difference betweem a two door post, 4 door sedan frame, and will they work on a 66 2 door hardtop.

The only difference is in the rear spring pocket
The 67 uses the small pig tail sping both bottom and top. So if you use it on your 66 you need to use 67 springs....

a 4 door frame is the same a two door frame.
the onlt differnet frames are the Conv,, there boxed and use a specfic trans cross member.
and the Station wagon and El Camino.. there 3.27 inches longer in the tail section...
and the El Camino is Boxed...

There are some visual differences in the '66 vs. '67 frame, but should not cause you any problems. There are a couple of body mounting brackets in the rear that may be located slightl;y different than your stock frame, but they can be easily moved/relocated.

The front of the '67 frame on the sides where it swings outward and downward has a different profile than the '66. Doesn't impact the frame swap at all, just different profile. Just compare the rear body mount brackets and move the '67 bracket as needed or the '66 depending on which frame you are using. '67 has a braket welded to the side of the frame and the '66 has the mount hole running through the center of the frame rail. Other than that it is the rear spring upper housing as already stated by WayneK.

I know this for sure as my '66 frame had a notch cut in the right side frame for header clearance and it was weak and flexing. I wanted it back to stock and used a '67 donor frame. The '67 frame profile was different in that area and did not match up correct as an insert. Had to "adjust" it to make it work. Always a surprise the first time.

Good Luck

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