Rob, you've actually got me thinking... keep one motor as-is, stock and reliable. Then perhaps take the one that needs TLC and build it up a little, since it'll already be opened-up and they're a suitable platform for such things.
That's a steal for $1300 US. Also,the '83 came with a big-end on the left side of the crank,an improvement(somewhat)over the '82. Although some '82s that were manufactured towards the end of the model year have the big-end crank,go figure.
Uggh,I was hoping you wouldn't be interested in modding....those engines can withstand serious power,but they're money pits. Ask me how I know
1st&foremost,the stator/starter clutch bolts need to be addressed. It's an issue that can't be avoided as the design is flawed. Nothing major,but some effort is involved. Then you're good for basic shit such as some nice Mikuni RS flatslides and 4-1 pipe,those add a solid 15-25rwhp+ depending on size.
They made under 100rwhp stock,but you could get 125rwhp w some RS 40s and a Kerker/Vance&Hines/Bassani(who remembers those?)4-into-1 pipe. But all the power is in the head,and thats where it gets expensive.
At about 140ish rwhp the helical gears on the primary drive/clutch basket become the weak link as the torque from the engine will side load the gears since they're on an angle and very bad things happen. Straight-cut gears on the crank/clutch and a billet basket are the required fix,but being the crankshaft is roller bearing and has to be pressed apart for the parts to be changed,it makes sense to replace the OEM rods with aftermarket...its BOOKOO bucks
I spent close to $1500(dealer pricing discount no less!) back in the mid-90s to switch to straight-cut gears/billet basket.
Don't let that scare you,once you see how much time/money it takes to get 140-150rwhp outta one of those engines you'll quickly forget all about making more power lol.
Before I get crucified,it's been 23yrs since I was drag racing my first GS I built
so some of the numbers I mentioned above may be slightly off(not by much though)...
This will be much more helpful for all the technical/performance stuffz: The GSResources
and there a few really good Facebook GS groups too.
I think you should definitely grab either,or both of those GS's...