Eddy 1405 tuning advice

So test drive sucked lol. Low speed cruise, surging. WOT seemed ok, no surging there. Building up to wot there were stumbles/surges.
Stalled once.
Backfired quite a bit
Only real difference was timing set to 12*, increased idle screw 1/4 turn to compensate for rpm drop. IMS screws out 1/2 turn each(Ds 17/8, Ps 2 turns).
Idle in park 750, vac 13"
Idle in gear 650 vac 10 1/2"
Timing 12*
Lash set to 0.018" int and 0.022" ex.