QwikGT - I wondered about that - and no, I moved the MAF further away from TB towards filter. I can change this and move closer to stock and see what that does.

Just got back from another hour of test driving and the RPM issue still exists same as before. More pronounced when AC on, car warm, in gear, coming to a stop. Struggles to find it's idle.

I received my O2 sensor and fuel filter today but want to sort this out before I throw other changes in the mix. I'll keep you posted.