Adam.......the M/S carb has 2-adjustment needles. The down-pointing mainjet is best set to 2-turns and LEAVE-ITT!!!
The side-pointing idlemix is adjusted for FASTEST idle, NOT SMOOTHEST idle. Understand the DIFFERENCE??? The behind the carb idle speed is adjusted for a SLOOOooow 400rpms. (ennythang under 500rpms is good)
The last time I adjusted the idle on my eazy starting 6-volt 52-8N, the idlemix screw was about 1/8-th turn. Remember, the side-pointing idlemix is BASSACKWARDS; out fer lean; IN fer ENRICH.
As for ignition points gap=0.025". A sparkie gap round wire can work iff'n yer careful. Remember to clean/polish the ignition points after installation and adjustment (0.025) Me? I use a clean $1-bill clamped between the points and pull. Iff'n yer really cheap, tear a strip from HEAVY brown paper grocery sack and use that.
As fer yer ruff-runnin' when warmed-up; yer weaksister ignition switch starts causing weak sparkies after about 15-mins. New switch, $15 (cheap) .........Dell, yer self-appointed sparkie-meister