All you need, mechanically, to do a rebuild is a pair of new seals and about 8oz+/- of fork oil. I'd start with 15W filling the fork legs to within ~3" of the top, fully compressed; then, fully extend the leg and install the cap, to trap air. If the fork hydrolocks before it can bottom out, remove 5cc of oil and retest...until it can just bottom out. If it doesn't hydrolock, more oil can be added to further firm-up suspension action. Stiffening it beyond that limits your options to 20 fork oil. Grab some cleaning solvent. Once the inners are removed form the outers, you're gonna find a lot of crap inside, that's gotta go. It's easier to metalfinish & polish the aluminum lowers while they're apart, same goes for cleaning/removing the rust from the upper portions of the inners. A little grease, or clearcoat will keep the steel from re-rusting.