Taking the blocks out and uncranking the torsion bars is a great place to start!

The alignment is a no-brainer

The rear glass might be as easy as using some silicone and sealing it up that way.

Tires - The BFG AT is a good choice, possibly another option may be the Bridgestone Dueler Revo.
In the P-metric sizes they actually carry a 50k mile treadlife warrenty (265-75-15 is right at 31").
You say you have a 10" wide rim? Might be a bit too wide for a 10.5" tire. It'll probably seat the tire, but IMO it'll look kinda funny. Sorta like the F250's with 7" wide wheels and 235-85-16's. PITA to get those tires to seat the bead.