95' NA Low compression / smoke on exhaust

[fredt2]

Greetings once again,
Recently my old engine on my 854 NA gave up, after 150k miles, lots of wear in the cylinder walls to the point of not being worth resleeving, so i got another engine from a donor car that had 70k mi on the clock.

i was unable to test the engine as the fuse box and fuel system was removed, I could've cold tested compression, but that probably would've been unreliable. I was able to put a bore cam inside the cylinders tho, couldn't see a lot but there wasn't anything outstanding.

Now I've already changed the engines, car starts normally but after running for a little while(1 min) a considerable amount of smoke starts to come out the exhaust. Glove test OK, currently running 15w40.

With the car warmed up, I was able to perform a compression test, with the following results:
175-125-150-125-175
I did a wet test on cyl 2 and it went up to 175.

Looking at the numbers, there seems to be uneven wear on cylinder 2 to 4.

My question is, could this be just the rings? Or is it more likely worn bores?

Is there any other tests I could perform without opening the engine?