Good eye on the frame, it is indeed an 18". I wondered if this might be too small, but I feel pretty well extended when I sit on it....then again, I have very little riding experience with a proper quality bike. Would something like a 21" be more appropriate for a fellow like me?
I already expected to put more into the bike than what I paid for it....for that matter, I just spent $28 on a frame pump and $7 on some spoke wrenches.

After some research, it looks like a decent entry-level MTB is going to run me north of $300 for used in good condition, a little more for new. I've seen mention of the Saddleback being about a $100-$150 bike with stock components and everything working......if I can put that much into it in parts and have a decent general-use MTB/hybrid for starting out with, I'll be happy.
If this bike would not really benefit from a nice suspension fork, I'll just go with a basic rigid. I see some NOS and used forks on ebay for $20-$30 (some off-brand, some GT, Spinner, and other known brands). For that matter, I suppose I could hack this fork into a rigid, but I presume it's heavier than a good rigid (heavier still if I stick some steel rods in it). The main issue with the fork is that the lower section is loose, worn bushings I suppose? I guess it's ridable, it just seems kinda shaky to me.
OTOH, if I figure out this 18" frame is really not a good fit, I won't put a lot of money or effort into making it fit. There are too many other good used bikes on the market (though not a lot of big frames, from what I've seen).
Thanks for the tip on the kickstand.....I never thought about it falling down on the trail, but that makes perfect sense! Hey, one less thing I'd have to buy if I end up going through with this project.
Matt