Take a look at the body mounts. Most cars need to have the rear floor notched out for clearance where the frame kicks up to go over the rear end. If you don't you have to put blocks on the body mounts to get clearance.
Ive seen some pretty low S-10s but i think most of them use hydraulics. They have dropped spindles available that will lower the front a couple of inches but that isn't enough to fix the 6 inch gap.
You could always change it to 4 wheel drive and put 33 inch tires on it and go mud racing.
Is it a finished car or a project that he gave up on when he couldn't get it right?
Whatever you have to do to make it right would be a lot of work and lots of money.
AL