Slant 6 hesitation or stumble

So you bought a new distributor from O'Reilys? Who knows how it is setup. They are usually assenbled from a mismash of parts. Do you have a dial back timing light? If you do, then you need to map the advance. If not, I would try advancing the timing 5* and see how it runs.

Not true if it's a NEW one as the only new ones they sell are from Spectra. That's the same Spectra that makes fuel tanks, sending units and "all that" and they're located in Canada and make all their parts right here in North 'Merica. Now, that said, before I left O'Reilly, All they had available were two A1 Cardone part numbers. One without the cap and rotor and the Cardone select with the cap and rotor. Both those numbers were reman units, not new. BUT, only one, the one without the cap and rotor was available, although both were in the system. I left on Easter Sunday, so, maybe the new Spectra units are available now, but "I doubt it". I fully agree though, any reman unit from any of these parts stores should be set up accordingly, as they are just slapped together. Plus any electronics they have are total crappola.