I can almost guarantee that the engine shop did not do what is needed to the distributor. It is not just simple springs and weights like a GM. The advance limiter slots are way too big and must be swapped with a smaller Ford unit or welded up to make them narrower, thus limiting the amount of mechanical advance. Then changing springs to get it all in by 2800rpm or so.
Tuning the vacuum advance is as simple as sticking the proper size allen wrench in the vacuum nipple of the advance can and screwing it in a few turns, then testing with a hand vacuum pump. There was a thread on here within the last few years with all the steps and how to set it up right.