Ok, I may have a total 'odd-ball' transmission mount. dunno for sure.    My
vanagon, an 84, came to my ownership with an Inline 4 (1.8l cabriolet, 1992)
hooked to a 5sp manual diesel transmission.  The mount at the 'nose' of the
transmission looks to be McGuiver-built from a round motor mount that's
connected to the chassis cross member and a plate that captures about 4
bolts from the tranny's case, right at the front.
  I am thinking the mount is inadequate.  I am thinking the rubber in the
engine mount portion is old and too flexible, and it has some cracks in the
rubber.  Laying under the van, I can take my hand and push up the nose of
the tranny, with little effort.  Going up hill on gravel, I get some wheel
hop and some clunking..I think the trans is moving around due to the torque
of the tires rotating the whole driveline.  When I bump start the van, I
also hear a clunk.
  Should I be able to move the nose of the tranny easily with one hand?  I
can lift it about 1/2" before it gets difficult.
  I have, and am planning to use,  a diesel motor mount and a new bracket
for the front of the tranny and I'm planning on revising the mount with the
new, stronger motor mount as a replacement for the old round flimsy looking
mount that's in there now.  A little welding for a new frame bracket to
accept the single stud  that's the chassis mounting point for the motor
mount I plan on using...
  Any 'gottchas' that I will encounter...?
  Other than the strange clunking, my present tranny works great.  Very
rarely, under hard acceleration with a turn, from a dead stop, something in
the driveline is getting torqued enough to cause a weird buzzing
vibration...Not good, but I think related to the movement I am seeing.
  I want to make sure everything is pretty stout, because I do lots of rough
road-dirt road-off road excursions...but not so far, because I don't like
the feel of the tranny moving around under load or with 'Big Air".....
  Don Hanson