Try using the stock Boge shocks in the fornt and the KYB gas shocks in the
rear.  I really don't like the KYB on the van because they are too stiff and
cause other things to break on your van instead. motor mounts, exhaust,
basically anything that can fatigue with getting jeerked around.  The softer
shocks should absorb this impact from the road.
I got a set of Bilsteins on my Westy, they're nice but the Boge are very
close.  Go with new Boge all the way around. Shop around

Malibu Tony 85' westy