xs500 where do i even start?

Hi guys, first post here so please be gentle.

A few years back i brought a job lot of xs500/tx500 parts. I won the lot on ebay for about £500. After driving halfway across the uk to pick it up i realized i may not of been able to fit it all in the van, a long wheel base merc sprinter (there was that much i felt like i was robbing the guy but he seemed happy to have the space again!) since then the frames, engines and parts have all sat in my parents garage much to their delight!! ;D the time has finally come for them to move away and it would be a real shame to scrap it or sell it all without having a good crack at getting the best out of it. so i'm here to ask what i should look out for, what parts are the best and any general tips and tricks when it comes to the xs500. I've worked with guys who have said its the best bike they have ever owned and ive also had a guy tell me that when he sees one he feels physically sick from the awful memories he has of owning one :-[ i plan to strip it down and cafe racer it, i'm a fabricator and welder by trade so that's the easy part really. Any help would be appreciated, thanks!

good luck with that

maybe start by seeing which engines turn over and shift through the gears, which frames are straight and not rusty, which forks are rustfree and straight. bodywork not dented, cracked etc, wiring looms that might be working, test elec components..... etc, you get the idea

put the good stuff in one neatly sorted pile, put the crap in another one, see how much good stuff you've got that maybe doesn't need too much work

i've been in the same position with XS650 stuff and CB750s and it at least enables you to see whether you've got the stuff to build something with lesser hassles, keep enough to build two bikes , build the best bike you can, keep the best spares and shift on the rest