How do you put a HEI distributor on a 90 TPI engine?

I am aware that the injection can be changed to a carb. by replacing the intake manifold, but is there more to the distributor install. than that; does the cam have the necessary gear for it or will that need to be changed as well?How do you put a HEI distributor on a 90 TPI engine?
The HEI will interchange between the two.But the advance is electronic on the TPI and you will then need a vacuum advance while converting to a carb.Do this by using an earlier distributor which will also interchange to your engine.How do you put a HEI distributor on a 90 TPI engine?
I'd go with a drop in Billet MSD distributor with a bronze or fiber gear since you more than likely have a roller cam. MSD makes a quality product for around $300. you get what you pay for in gas savings.