Advise Swapping an 8.5" corporate Into a 1966 Le Mans ?
 

Greetings friends, I need some help with swapping an 8.5" corporate rear end into my 1966 Pontiac Le Mans.

In 1966, it was the last year Pontiac secured the rear coil springs on the axle tube, using the bolt on plate. The top of ths springs used a wrap around insulator.

So, now, I'm useing the 8.5 I just had rebuilt but need some information.

1: if it's now the later rear end, do I just use a later insulator on the top of the spring which is like the 67 and newer?

Do I order springs that fit the normal 66 Le Mans / GTO, or will I need taller springs for the normal ride?

I tried installing a new set of 72 Wagon springs, but now the normal 66 shocks seem to short to mount up.

Thanks for any help anyone may have on this swap. Good day friends.

Mike in Oregon