PS pump belt tightening question

[SuffolkD at aol.com]

Liser(s): 20V Avant 3B

I'm at my wits end in tightening the PS belt.
Besides it (belt) being the wrong size (maybe too big).......I'm stumped.
Loosen PS mount on block, tinker with adjustment screw...back a forth no luck.
It takes 4 13mm wrenches and sockets just to do all the nuts...............
Adjuster: Cleaned threads with wire brush, oiled, spins smoothly in both 
directions.
Snapped the long adjuster bolt w/1/4" socket set geez....now I'm on the spare 
bolt.

I can get it somewhat tight but then the belt has too much play during 
adjustment.
any BTDT's?  I conquered the alt (thanks Peter) but dread undoing all three 
to redo this one again........don't see an adjustment to the center crank 
pulley.
................................At least I didn't crack the radiator hose 
nipple.
-Scott by BOSTON