1985 60 hp evinrude timing question

[74 supersport]

I just purchased a 1974 starcraft ss with a 1985 evinrude ,the powerhead was rebuilt and I just went through the break in period in which it ran horrible on the double oil,after running fresh fuel it was hard to start ,would stall at idle,would stall when put in gear ,if I could get it to stay running it would stall on initial accel, if i could get it to throttle up it would start missfiring and bog down,could never obtain full throttle before it would lose power,fould plugs and eventually stall,I performed the link and sync procedure and it improved but still ran horrible ,yesterday I couldnt keep it running on lake and in desperation against my better judgment I increased the maximum advance. the engine is still hard starting, idles rough and surges up and down,seems to be dropping a cylinder and still stalls when put in gear but now after an initial slight bog down I can accelerate to full throttle and it seems to run 90 % better,I took it very easy and did not run at full throttle too long as I am concerned about piston damage.ran 1/2 tank of fuel through at this setting but I know now I am way too far advanced.

question 1 ,on link and sync I have the throttle plates opening at same time as spark advance lever moves,is this correct?

question 2 ,have I caused any damage from increasing spark max advance and running a half tank of fuel through?

question 3,is there any setting for idle timing ?

question 4 ,am I overlooking something ?

I have read the posts in the evinrude section and have the reeves method of setting timing so im going to get a spark tester today and do the procedure but any input would be awesome,thanks