The MP can work fine.

If it has a bronze colored tower where the rotor plugs on, it's a mallory unit and easy to adjust with basic tools and some drill bit shanks. Iron colored it requires some welding. The slot lengths are on the site and other places to set mechanical advance.

IMO, get it hot and see how much initial timing the engine will stand before kicking back or dragging on the starter. Once you find that point, you can dial in the rest.

It should run a lot better once you get the idle sorted out. I had a 360 with a similar cam, 20 initial 14 mechanical. Idled like a nice sleeper car.