help with tuning an AED 750 Ho

Ok, so I got some cup tip set screws a while back and drilled them for .031s' I put them in and drove around and still getting a slight stumble at cruise 2500 ish. I disconnected the secondary linkage to see what would happen cruised around and the stumble seems very slightly less. while I had the secondary unhooked cruising around the AFR gauge was showing 13.2 to 13.8 I'm not sure how well I trust the thing. seems if it were that close it would cruise and have no stumble at all. Also, with the secondary disconnected and at operating temp, sitting in the garage, if I run it up to say 3500 to 4000 and hold it level It will seem to run smooth and then get a pop. wondering if that has anything to do with it or what is going on there, I'm thinking it is from whatever is going on with the IFR or AIB. Just trying to give enough info for anyone that can help. Is there anything I can check or do to figure this out more? Questions; Should I go down on the IFR in the secondary as well? Should I try going down a bit more on the primary? or should I go up on the IAB ?? And if so do I need to do the secondary as well? any help at all would be great. I am trying to get this running and cruising well to take to Branson cruising lights in a few weeks.