Re: M.S.D. ? about pick-up in dis.
I put an MSD 6A in my zook and learned a few things. The MSD will accept a variety of input signals, including a low level pulse from a magnetic pick up. If your distributor is not sending a good signal, I think the likelihood is that your igniter has a problem, because I don't think much can go wrong with the magnetic pick up except for physical damage. Anyhow, I confirmed by experimenting with a spare distributor from which I had removed the igniter, that the MSD box will fire on just the signal from the magnetic pick up. You can download complete installation instructions in Adobe format from the MSD website, and you will probably learn a lot like I did.
I decided not to use the modified distributor and used the "other" (higher level)input on the MSD box. My reasoning was that if the box should ever burn out, I wanted to be able to revert to the stock system without removing and replacing the distributor. I went to my favorite junkyard and picked up the connectors I needed to put the MSD components in the system without cutting any Samurai wires. I also had to use an MSD "fuel injection adapter" which the seller gave me, but which I had no idea how to use. One phone call to the MSD help desk cleared it all up (except I still don't know exactly what it does other than make my car run great). So, what I have now, is the MSD box and fuel injection adapter (I don't have fuel injection), hooked up with stock Sammy connectors, triggered by a stock Sammy distributor. If I have a problem with the box, I just unplug two connectors and reconnect the stock pair. I also carry a set of plugs gapped to stock specs because with the MSD, you will run a much wider gap.
MSD does make distributors, but I don't know of one for the Samurai - it would be very expensive anyway. Good Luck.