What was done to freshen up the engine?
Were the pistons replaced or heads milled?
Just curious as the piston to valve clearance might be tight with 242 exhaust duration @ 0.050?

I think you said cam was installed straight up? So we really don't know the exact installed position? You could maybe just do a quick check that the intake valve is at max lift around 102-degrees ATDC?

I'd start with the basics, pull the plugs and inspect them, then do a compression check. Leak-down check if you have the equipment.

If that looks good, you do need to re-curve the distributor as mentioned earlier for maybe 18-20 degrees mechanical advance in the plate, and around 16-degrees initial timing at idle (with no vacuum advance.)
Idle will likely need to be higher than normal too, and at idle the carb may be exposing the transition circuit. Check how much of the transition slots are exposed. You might have to drill the throttle blades if exposing to much of the transition circuit. Not sure if the drilled throttle blades is still the correct tuning adjustment? I think the Demon carbs have an adjustable idle air adjustment, and there may be a better way to correct that?