Hei conversion from pints need help... what am I doing wrong.

Car is still new to me. Bought it as a project. 70 duster 318 converted from slant 6 by previous owner. Car fires up with old points style distributor, but does’t rev up very good and around 4,000 rpms when driving breaks up really bad like the car is missing. I thought It may be distributor related so I pulled out the points distributor and the rubbing block on the points is severely worn, when I spin the distributor it barely opens the points. I’m surprised it ran at all.

so I got an electronic mopar distributor and added the hei bracket and wired in the hei. The two wires to,feed the hei converted distributor are labelled b and c on the hei module. B being battery or positive and c being coil or negative.

My ignition coil has a dark blue wire which I believe to be positive and a black wire negative. So I wired the hei b positive to the positive coil side. And hei c to the coil negative side. So car fired up but took a lot of cranking and messing with the timing of the distributor to get it to run. It idles fairly well, but will not rev up at all. If I increase rpms past like 1000 it wants to stall out.

‘I have an ecoil I was going to wire in for the hei conversion but thought I’d try with the factory coil for now to make sure things worked first.

what am I doing wrong. Help me trouble shoot.

Your help is greatly appreciated.