Rebuild Runs Rough

was the efi and cam etc all the same as before the rebuild?

Is it possible you are too lean?

vacuum leak?

what you are describing sound just like my 150000 mile ago rebuilt 273 , 1 cyl is in the 110 range and one is in the 120 range and the rest are in between. I leaned out the carb thinking now that I'm at 5000 feet (was a sea level car) I would need to do that. at 2500 rpm it seems to be misfiring and 2500 rpm, Hydrocarbons are 1000 greater than they were before the jet change. with less advance it seems to behave better but not great. drivability is not effected that I can tell.