Ok,

What you are seeing there is a 13mm bolt and nut holding the little block into the U shaped bracket. Start the nut on the bolt but do not tighten it. There should be one more long 13mm nut and bolt on the bottom side, stick that bolt in and start the nut, do not tighten it.

Now put the 10mm long bolt through the bracket and thread it into the square block. Now here is the trick, you just tighten the 10mm bolt. Do not pry, push, or attempt to move the alternator. As you tighten the 10mm nut, what you do it move the alternator away from the the engine along the U shaped groove as the bolt tightens. You will be cranking for a while, and as the belts start to snug up start checking the tension. At no times should the 10mm nut be under much stress by the way. If does seems to get streesed one of the 13mm bolts and nuts are too tight or the belts are too tight. When you are happy with the belt tension only then do you tighten the 13mm nuts and bolts.

Then you repeat the same process on the AC Compressor and the power steering pump. Loosen the 13mm bolts and nuts that go thought the accessory bushings, and use the 10mm bolts to snug up the belts. There is a hidden oval headed nut on the back side of the compressor, slide you hand down the back top bracket (behind the power steering pump). On the back side of that oval head is a 13mm nut you need to loosen. Same thing goes, use the 10mm to tighten the belts, and then get after the 13mm bolts and nuts. Do the AC first and then the power steering belt.

That should get you there, and one more tip. On the bottom of the alternator is a big ground wire that connects to the engine block. You want a good strong wire with good connectors on there. Replace it with at least a 14 gauge wire and new terminals if not sure.

Good Luck and hope this helps,

Paul