convertable top frames
 

How do you ID a vert top frame ? I have a frame that is supposed to be a 68-72 chevelle but was told it is not that it is earlier , is there something to look for ? The only part # I found is on the top latch 5717166 RH and I could not find that in my part books. Is there other places on the frame to look ? How much bigger are implalas or smaller for camaro ? I have never owned a vert so I am out of my area.
Thanks
David