I thought I'd share my experience with a product that made its way onto my car. The item in question is the whiteline replacement rear subframe bushes for s13/14/15 r32/33 (and possibly others)
I noticed an annoying clunk from the rear of the car under acceleration/deceleration but not changing with suspension load and figured it had to be the subframe bushes. I considered pineapples (metal and rubber) and other rubber replacements but thought, bugger it, if Im going to do it, Might as well do it properly.
The bushes themselves are a solid urethane item with a metal sleeve. The idea is you remove the old bush and metal sleeve and drop these in. Sounds simple enough....
There is no way this can be done without the subframe coming out all the way, thats a pain but not undoable. I actually tried to unbolt and lower the subframe with brake lines/cables attached to get enough room to lever the old ones out, but it became apparent that wasnt going to work and they wouldnt budge and it went into the too hard basket and help was sought via dumhed.
Getting the old ones out is a bastard, It involved drilling out all the old rubber bushes (or rather, the rubber bits left....2 had the inner sleeve completly free floating) the hacksawing out the old sleeve then levering the cut edge out before the old sleeve would drop out.
Getting the new ones in was worse. A hammer, grease and heat to the slot didnt work.
A frankentool was designed by the guru which comprised of two camber plates, a custom machined plate to match the contour of the bushing, a 3" exhaust pipe and a giant bolt and nuts which pressed the bushing in.
This destroyed the exhaust pipe....yeah it takes a LOT of force. Replacing it was an old piston! This got them in after cutting the bottom plates so the press could be properly centered.
This process took the better part of two days, not including getting the subframe out in the first place....
So. While the end result is fantastic, the time outlay and MFAT* is obscene so unless your bushes are completly dead, go with pineapples, if they are, consider getting someone to fill the old bushes with urethane epoxy (there are gaps in the factory bushes).
*Mandatory fucking about time