classic motorcycle forum

Powder coating usually involves some form of blasting as prep. You sure you really want to that with OIF?

Something's happened to the bottom pic....it's been stretched across the page and the bike looks elongated.
Hang it on the wall....it's not a bike anymore.

I seem to recall that the four-stroke 500 was allegedly quite a bike, but the two-strokes are just typically Commie-era crap, and the later the worse. Depreciation resembled the immortal stone-off-a-cliff plus they were totally sh*t to ride.
What would be the point? 

The temps should be comparative as they don't mean much in themselves.
Is the slide not as specified in the manual?
It's a common enough bike and you shouldn't have to do plug chops.
(Incidentally, I don't know if it's correct or not, but some American tuning bloke posted a while back somewhere else that plug chops are only vague at best on ethanol fuel. Can't rely on them anymore it seems}

Other than "EI units you might buy in the future" there is no advantage.

That is one lucky bike! Better bikes than that were being weighed in 1980 so this is a lucky survivor.
With respect, until you understand about A/Rs etc you can't make diagnostic decisions what is or might be wrong with your bike.
Is there no-one locally who could give it a swinging kick for you?
As has been said, these bikes are simple, and it never pays to compare with later bikes and make judgement calls based on them.

Get hold of a manual (possibly download an E version if nothing else) and see the early pages as there's normally starting instructions, as in where to position the A/R etc. Look and see what the basic carb settings are in the manual and check those too, and although I doubt it's ign related, check the timing, points gap and give it a new plug too.
That bikes looks restored but not run...it's very clean.