which of these two diagrams do i need to follow to use my stock tach and everything? i am a little confused here and need some help. thanks.

first one, and it's 1,000,000,000,000% easier w/the harness adaptor. Trust me on this one.

Yes, get the adapter harness.

Your ICM and ECM Do the same exact work as the MSD boxes It is redondant to put one on a computer car. There are no gains.

I gained a smoother idle.

Well, you're going to love me with this comment, but-

You spent $200 bucks to get a smoother idle? Was the car staling on you? Adding an MSD bos instead of fixing weak stock components is not a good fix, the MSD box is a marketing gimmick. You probably changed your plugs when you installed it too right?

There are no noticable performance gains from an MSD box. It may show slight gains on a smog computer but no gains in the 1/4 unless your other components are shot. Just fix the other components.

I should also note: That I used to be given any MSD products free for my Vette when I was Sponsored by Centerforce. Mike Hayes installed an $800 MSD system in the car an it ran the same. I actually caused use so much grief from failures (not reliable) that we finally pulled it after 3 different boxes in a years time. I'm back to the mechanical points distributor (Three bearing shaft) which I originally ran reliably to 8500rpms for years.

actually, I got it for $100, and installed it after the engine fire. I mainly got it for a) the looks , b) help improve emmissions (since it's subject to nazi e-checks ). And nope, same plugs in there before & after. Although it doses have new wires, egr solinois, & MAF now

I'm going with a 6AL+BTM.. but only for the limiter and boost retard.. so if anyone can point out a good stock-compatable limiter and boost retard I'd be very appreciative

I've heard multiple gripes about the MSD and Accel boxes all being $200 fuses...

When i installed mine i noticed some more power not enough to say omg but some. I did how ever notice that my car had a better pull at high RPM's. I did not change the wires or plugs jsut simply put the msd box in my car and that was it. When i disconnected it because a ground wire came off i did notice a difference in my car. ISo far i think the best mod i have done are the underdrive pullys.

i want to msd box mainly for the 2-step rev limiter which i don't have yet but i do plan to add. i went to the junk yard today and picked up a couple of plugs so that i don't have to chop up my wire harness and i don't have to wait for a harness to get here, $2. underdrive pullies, i noticed nothing except that my power steering pump pulley does not rattle as much as it did before.

I NOTICED A INCREASE IN GAS MILAGE AS WELL AS POWER INCREASE. SORRY ABOUT THE CAPS IM AT WORK. I DO WANT TO TRY MALLORYS IGNITION ON MY 68 FIREBIRD SEE IF THERE IS ANY DIFFERENCE

i SPENT THE 20 BUCKS AND GOT THE CABLE TO HOOK IT UP

i spent $2 and made the harness.

Fast RS: does your tach work?

Yes it works perfectly. FYI one of the connectors on the coil will not need to be hooked up. I belive that one is for the tac. Call MSD they should be able to help you.

ok, i'll try giving msd a call tomorrow. what i did was i went to the junkyard and picked up the plug that goes to the distributor and the plug for the coil and sliced them onto the msd box wires like the diagram shows to do on the msd site (link above to go straight to diagram page). i got it to run on the 6a box but had no tach.

Uhh you cut a wire that went to the Dist you mean the ignition module????? The only wires you will need to be concerned with are the 4 wires that are on your coil.

Hey where the little black cord is there is a screw i belive with 3 wires in it. You need to cut one of those wires for your tach to work. did you do this? I cant remeber what color wire it was i want to say white. But it will say in the manual you got with the msd box

i bought the 6a box used, didn't come with instructions. i got the diagram from msd's website though. i'll take pics today of how i set mine up and post them so that hopefully someone can tell me what i need to do.

If MSD sucked soo bad why are they in business still. I noticed a little difference in my cars performance i think a MSD Ignition should be one of the lastmods.