just rebuilt runs bad

Go to your nearest auto parts house & get a point type dizzy, set the points & drop it in, hook up the vacuum advance, trust me on this, you will be able to rule out all the electronics you installed, it very simple, you'll need a stock coil though, the dizzys are not exspensive, hook up the ballast, the brown wire to the + coil, distributor wire to the - side, set timing, don't be surprized if it fires up & runs like a raped ape, if so, THEN you'll know its either the Box/coil/distributor, I wouldn't trust a used dist., especially a mopar elec. unit, I'm guessing its in the pickup coil, they will cause all kinds of issues, includeing backfiring through the carb, its fireing when its not supposed too, simple as that.

Always check the obvious 1st., don't start digging deep for problems, it will get exspensive real fast & the problem still exist, I'm sure the machine shop did there job & all is good on there end.

The lifters can/will bleed out & clack when its firing in the wrong pattern, happens all the time, once you get it sorted out, you'll see the lifter/lifters will calm down, take a deeeeeeeeeep breath, its something simple & over-looked trust me. BTDT.

Let me add this, DO NOT use the MSD coil on the point dist., you'll fry the points in know time, you can get away with a factory elec. ignition coil, but one for points is better, Now you won't have to keep the parts :D, I know its wrong but oh well, if the problem is fixed with the points, just pull it out, clean it off nicely & bring it back, don't get grease on the box, the points shouldn't show any wear in a short time, just tell them you found the problem & didn't use the parts, they will give you a refund.