Not to detract from this conversion in any way, but there is another way to get the same results just by replacing the distributor.

I did this on my 86 D100 318 to eliminate the ESC computer. I got the distributor from Ebay for less than $60 and hook up is as easy as a hot wire going to the coil and the two wires from the dist hook up to the coil. It uses a gm style module (although not an exact gm copy, the terminals are on the side instead of on the ends) mounted under the little housing on the side. I used an MSD Blaster 3 coil that did not require a balast so I did not have to add one, or you could also use an e-coil which the sellers also offer. Doing this swap has been a huge improvement over the stock system. It has helped with the hesitation, though I still have some carb issues, the idle has smoothed out considerably, and the tach needle is now rock steady.

Although I went with this option with my small block, when I get the 440 swapped in (IF I ever get the 440 swapped in. Where's the OverHaulin' gang when you need them?!) I do plan on using a stock distributor (or maybe a billet replacement, eventually) and the gm HEI module conversion as outlined. I know this HEI distributor is available for the big blocks also, but I don't really want that big housing sticking out on the front of my engine. I would prefer something a little more stealthy.