E28 535i (M30) Engine Mounts
The Plan
To replace the M42's stock hydraulic engine mounts with the solid rubber ones from an M30 powered E28 535i.
The Reason
The M42's engine mounts are very expensive (around $110 EACH), and are fluid filled which can make a mess when they fail. The main problem with them is that they are not as reliable as solid rubber mounts, nor as stiff.
The E28 535i's mounts cost about $35 each, are of the same dimensions as the M42's and will bolt right in. There will undoubtedly be some increased noise & vibrations transmitted into the cabin, but nothing unbearable.
Parts Needed
TWO E28 535i Engine Mounts [PN 11-81-1-132-793]
A writeup of this procedure will be available in the Articles section in the near future, though doing this is pretty straightforward.