Decoding frame
 

I have this frame, bought it as a 66 GTO frame. The only #s I have found so far are on the rear where the photo is circled. Stamped 7K606747.

Any ideas? Could it be a 67 made in KC?

My 67 KC car was stamped there with 7K143XXX.

I was thinking it may be a 67 KC frame

The 66 frame has the large opening [ about 5" ] to engage the top of the rear springs. 67 & later had the smaller opening to take a pigtail end.

Pretty hard to be definite from the pic, but does look like the larger 66 opening.

I'd guess 67.

Here's mine.

https://forums.maxperformanceinc.com...1&d=1565431058

Here's his.

https://forums.maxperformanceinc.com...0&d=1565391559

Definitely '67
 

Here is a shot of the larger '66 spring pocket noted above,
Also showing the correct spring insulator for said pocket.
FWIW all you'll need is the '67 Rear Springs and that frame will work fine.

Yessir looks identical to yours.