It wont take much Bill - refill the shocks ( dont know what pistons are in there so open them up ! ) check the diffs are ok, oil the U/J's, bung on some mini pins or spikes, an old 14-19 s/d/t brushed motor and your away
Enough to start with anyway - otherwise take an afternoon/long evening to strip & rebuild it. Wont take long, they are easy to do.