I hope some of the tools are metric, but if you have it mostly stripped down, then I guess they are. You will use alot of 8,10,12,14,17MMs. It sounds like you can handle wrenches too, that helps..LOL. ONLY use quality full synthetic 2-stroke oil, Golden Spectro, Belray H1R, Klotz, ect. Avoid Valvoline, Penzoil, boat oils, weedeater oils, ect. You can saftly run 40-32:1 mix with the quality oils. The manual calls for 20:1, but in 1985 there was not good synthetics avalible.
OK, the compression gauge is fairly common and cheap. (Ebay, pawn shops, even parts stores and Wallyworld)I regularly check my compression after rides and write it down. It gives a great story about the condition of the rings. 2 strokes use up rings fairly quick(1-2 years) with lots of use. Its also a great way to tell if something bad is about to go or gone.
The micrometer is not nessisary as other tools, but when checking bores sizes, belt widths, wear on parts, ect, thats when it comes in handy. Harbor Freight has a nice digital for $15 that does metric and standard. Its a dead ringer for the Craftsman that costs $100.
2 strokes are fairly touchy about being properly jetted. Too rich and it blubbers alot and fouls plugs, too lean and you will sieze the piston and probably have to buy another.
Smart man getting the manual! You will find alot of your answers there too.
You can find alot of cheap used flat slide carbs on Ebay. Do a search for CR250 carb, CR 250 carb, TRX 250 carb, Keihin carbs, ect. Most of the carbs are larger than the stock 32MM round slide. I personally like the 38MM airstriker and 39MM PWK, but my engines are ported, piped, and built up to breathe. We can get you there too.
I would like to see some pictures of the 350 in general, then a picture of the exhaust pipe and silencer, liq head, carb, reeds, intake boot, airfilter setup, and (intake ports, exhaust ports, transfer ports and sleeve) if you pull the jug.
I am all about saving as much money as possible so I do my own work when I can.
Hope this is helpful to you. Keep posting back with anything,
Gary