The front mount just as you describe, but there should be some large washers that support the bushings along with the nuts. The optional rears for the 3800 used what they call a "bayonette' style upper mount, commonly called a stud mount. There was a stud on the top of the shock that fit into a cup mounted to the frame with 2 bushing and t special washers. Very similar to the front shocks on a late model full size or S10 2wd. I'd be hesitant to say you'll be able to find stock type shocks, but perhaps you could adapt shocks from a later 1 ton. You will have to fabricat the upper mount according to what style upper mount it has.
