Great, I ordered the wire harness and heat shrink solder connectors.

I unwrapped the wires back enough that I'm not seeing a splice of the red and white wires. I'm not sure this control box is the same as what we're seeing on MSD's site. I haven't seen a Multispark 6AL anywhere. But at this point I don't see a black/orange wire or a Black/Violet wire coming from the box.
But there are Red and White wires. I guess I have to remove the box.

This is my model box on Ebay. The wires look like mine. Red and white wires can be seen. I'm wondering if the wire colors changed after they stopped making this ignition box.

Black/orange+ to (violet) and black/violet- to (green) from distributor. At the plug it changes from the MSD box to green and violet. In that picture the plug with the green and purple wires above the box plug into your distributor plug.

When I type in model #6420 (which is on the box) on MSD's site nothing comes up. The only thing close is this model which isn't the same but it is Multiple Spark Discharge. The part # Wayne Ridley has for the box is 803033. MSD tech said that isn't in their system. So, Holley bought MSD and maybe some older stuff wasn't kept in the system.

Either it was hooked up wrong or the wiring was changed between the distributor and box. The diagram I sent on the last page /post #811 shows where all the other wires go. The one you ordered on Ebay has the plug with purple and green wires that plugs into the distributor plug in the top of the picture.

I took the box off the fire wall thinking I could unplug the wiring harness. Theres a plug with the green and violet wires but the rest of the wires are hard wired inside the box, no plug. The pic is the diagram on the back of the box. The green and violet wires I marked their location and they were water temp sensor from the intake manifold and another sensor on the manifold. So, At this point I'm looking at  A new Digital MSD6AL box #6425 for $350. The condition of the wiring is so nasty and the wires that are color coded  are going to the wrong place in some cases and have been spliced in multiple areas. I'm thinking starting fresh is the way to go. What I don't understand is it was working the way is is wired.

This is what I'm considering.

I personally know of 3 that failed in the last two years. The older ones like yours were far more reliable.  Your diagram shows green and purple to magnetic pickup(distributor) coming out of the bottom. If you have to, can you take the cover off and wire as I suggest?. The green and violet wires to the sensors have nothing to do with the MSD box.

I appreciate the input! Looking at the wiring after unraveling all the tape; it is too sketchy for me. The way its run thru the firewall it looks like they did it the way the AC hoses were done, some kind of filler as opposed to a rubber grommet. I can't unplug the wires as they are hard wired. I can't turn or move the box much because the way the wire bundle is run/attached to the fire wall. It's a mess with a bunch of spliced in random colored wires. (some of which aren't ignition related) And they're all absolutely soaked with oil. So, for my mental wellbeing, I'm better off starting over with new. If I could pull the box and wires out, put it on a table and figure out what each wire is, I'd attempt that. But, I can't so with my zero electrical know how, a new box with instructions and new wiring harness is very appealing.

Scott, It would be easy on the bench. You cut off the wires about a foot away from the box. You would cut the plug off the new Ebay harness and match the colored wires by size and use the solderseal connectors. Sounds like the whole car needs to be rewired! We are going to use a Speedway 12 circuit wire harness in Jon's car. The diagram on the back is really the same as the one I sent, only the distributor plug is separate. None of those wires need to go through the firewall. You just need to find a wire that is hot with the key on. I'll send an image of the 4 pin HEI on another engine similar to how we mounted Jon's. You could mount it on the firewall or fender too.  I think it is a better option and much less expensive.

4 pin HEI:

Here's our harness:

https://www.speedwaymotors.com/12-Circuit-Mini-Fuse-Universal-Hot-Rod-Wiring-Harness-Kit,2352.html

OK, I appreciate the help. I think if I pull the box and wires out, I'll then be able to see what's goin on. I think they wrapped all the wires going into the engine bay together; that's what makes it confusing to me. There's not a bunch of ignition wires to deal with. So at that point I'll figure out which direction to go. Thanks!

Didn't get the ignition box out today, lost power for a while. But at least I got a package.

Cool! There is red, black and white heatshrink to cover the splices and make them almost invisible.

https://www.ebay.com/itm/374963966998?_skw=white+heat+shrink&epid=8037953461&itmmeta=01KRQ4MY83ZRAB8ZF1E3QDY68A&hash=item574d981416:g:z8QAAOSwclJlGop9&itmprp=enc%3AAQALAAAA8GfYFPkwiKCW4ZNSs2u11xDgJnbalSN9yLrRGLm6nst1qQHHARPQAymQiJ%2F2f9B0WMOgKd7tl14%2BPDoYlPALya4DIbvoeZ18rVyvrB4FO0mNf1E5jZLbc9Sds3EaSwQ0S%2B58TZmFjzZxmWPxmU2gH%2BbsFlqjl8j%2Bg7gO80FSE1anNc5RsP%2BrFM5wP07abkahokNwfZHcyyCl--VrhrhqcFIckcgyrpTvUBtx%2BvkMk3Rm%2F2PLE9O4FkQTQpdqwiQl4BOnajb5eGgfCSXYCWRGdFhIePAQJhjqXvjBnM9u8QHkkQ83g0lOGw%2B9R%2BBv%2BfBFsw%3D%3D%7Ctkp%3ABk9SR6Lk0-TFZw

Nice! Another package coming.