The pump is new from the kit, seems like it’s leaking fuel on the base gaskets now, (it’s back in the car).
I've dealt with a few of those
Holley carbs. So, the pump housing is leaking. Needs to be pulled, and check the sealing surface. Probably not flat! It takes lapping the surface, until it is flat, so it will seal.
Same thing on the base surface of the carb...if not flat, lap it in, until it's flat. Bore sizes change (on any carb) depending on the cfm size. And, it needs to work with the manifold, your mounting it on. No gasket, set the carb on the manifold, work the throttle arm all the way to WOT (wide open throttle), to see if there's any binding. Shouldn't be. If there is, wrong carb or wrong manifold. A spacer can be used, made to fit, so all four throttle blades move freely.
One other note...any time you re-adjust idle speed, you have to re-adjust the pump arm gap.
This stuff ain't rocket science, but Holleys tend to be a little harder to dial in, unless everything is perfect.
Initial timing...assuming you already know. If you have a vacuum advance, before you set initial timing, you pull that vacuum advance hose off the carb base. Cap off that port, then adjust initial timing.
Still don't know, why your having problems with understanding distributor mechanical advance, and working with the numbers. Anyway...another day.
Bee1971 is giving you some good advice! But, basics have to be dealt with, too.