[sick472]

It looks like you have plenty of room to get a straight edge in there. Place it firmly up against the faces of the pullies so that it is trying to touch the rim in two places on each, preferably as close to the center as possible (it won't be close, but at least not on the outer portion of the rim). If it's perfect...it will touch both pullies in two places, it not, you've got some adjusting/shimming to do.

My 85 K20 would squall at the shift point from 1st to 2nd. The pullies were out of alignment due to a broken AC compressor bracket. The alignment was off visibly at 3 feet away with the naked eyed. Once aligned and tightened with a 1/2" of belt slop using my thumb to apply about 10-15 pounds of pressure...squall gone.