Moving forward that was a part of phase 3, specifically MEFI retrofits. I'm trying to keep scope creep to a minimum at the moment.

I'm waiting on the MAP and Coolant Temp Sensor connectors, but here is an example of the last 1/2 of the top side of the harness.

https://cimg0.ibsrv.net/gimg/www.off...e5317d8adf.jpg

looks nice, definately a market for it and theres a need. On the Mefi stuff, AEM has been selling a jumper harness to switch from a mefi4 to AEM controller, about 2000$ for harness and ECM, I guess quite a few sand rails had mefi4b on them, it could be repinned in my opinion to a mefi3, have never seen one in person or reviewed their software, then, AZSM claims they are building a mefi to holley harness but again, havent seen it available yet and IDK if there buildingit for a 1/2, 3 or 4 which all are wired different.

That's the reason I think that it would be better just to make a harness that will work for 454/502 and 500EFI. They are not too far different from each other that they would require much in the way of changes between them.

I had considered making a basic harness and then using plug in sub harnesses to adapt to different applications, but there are more differences than similarities so it will just have to be two different part numbers.

Been working through getting a couple of final terminal ends to finish the harness. Another issue I have been trying to solve is how to get around utilizing a dual sync distributor. Having this new crank trigger wheel is a huge step forward.

I present the 525EFI 60-2 crank trigger!
https://cimg7.ibsrv.net/gimg/www.off...f6f2e6bf2c.jpg

https://cimg0.ibsrv.net/gimg/www.off...d3dd7f1665.jpg
All the 525 crank trigger wheels I've seen look like this.

Correct! The issue is the 60 -6 wheel used with the 555 is not supported by any aftermarket EFI computer (that I'm aware of). Holley supports 12-1, 24-1, 36-1, Chrysler 36-2+2, one pulse one fire, and 60-2.

Without one of those wheels the only other option is to switch the cam sensor/oil pump drive over to a dual sync distributor which is almost double what the replacement crank wheel will cost. Using a 60-2 we can maintain the same resolution as before while utilizing the factory sensor setup.

It will be a nice option for those that want to modify their 525s when they rebuild. Allowing them to do their own tunes. It will definitely be a money saver not having to replace all the sensors. Doing a custom tune on a 555 can be a bit challenging, and time consuming.

Exactly! These have been my primary goals with this project. A cam and injector swap was a PIA, not to mention adding cubic inches or forced induction.

I have the mefi4 to aem infinity 308 jumper harness if your interested. I was going to use it with my mefi3 harness and re pin it but ended up building my own engine harness. Lmk