difference between GM's b-body and d-body?

[shrike77]

Hello,
first post here. Maybe someone can help me with some info.
I was wondering what are the differences between GM's D-body and B-body. I know they are very close but I would like to upgrade the suspension on my 1987 Brougham. Yeah it doesn't sound right I know.
I am contemplating adding a sway bar at the back, change the one in front and upgrade springs, shocks and rear trail arms. I was looking at the Hothckis products but they don't know if their products would fit my car.

There is also a Buick frame stiffener that can be used on B-body cars, but can it be used on the D-bodies?


Thanks

[novaderrik]

they are the same car with a little extra length added to the longer wheelbase on the D body.

[shrike77]

they are the same car with a little extra length added to the longer wheelbase on the D body.

Thanks,
So I can use exactly the same suspension components at the rear?
I checked on rockauto.com and could only compare some parts in the front. Some of them seem to have different part numbers.
But if I were to buy the rear sway bar and trailing arms, and shocks from let's say Hotchkis for a b-body, would they be a bolt-on upgrade for my Cadillac?

[shrike77]

Any braces I can install to also stiffen the frame?