Still hesitates off throttle...

That's a lot to digest. A lot of really cool history there also. Thanks.

First off, yes. It is a 68 4dr auto dart.

When I rebuilt the carb, I did give the spring a bit of a stretch. I usually do when I mess with things like that but to be honest I have no idea what a 'good' tension should feel like for that particular spring. The former owner gave me stacks of records from when it was sold new till now and I know there are at least 2 carb rebuilds done by a mechanic in there somewhere. I know that doesn't hold much water, but it's something.

I can't tell you if the car came with the CAP package, but I can tell you that none of that extra stuff is there now. There is what looks to be a 3/8" NPT port on the number 6 intake runner that is plugged with a hex plug. I would assume this would be for the fat hose. Vacuum advance hose goes directly to the port on the passenger side of the carb in between the 3/8" PCV port and the accelerator pump linkage. The distributor has been converted from points to electronic with a modern kit. Says NV5M on it.

Just for fun I just put the initial timing at 5 ATDC, 0, 3, 5 and 7 BTDC and it is happiest at 3 BTDC. 5 AFTER was almost undrivable. This was set with vac disconnected then connected for driving.