Hey everyone. I've tried searching but don't seem to come up with quite the relevant threads. If someone knows this has been covered before please send me in the right direction. I've established that the tacho wont work with standalone aftermarket ecu, but can if modified? Some of the links to how to fix the problems from old threads dont work anymore so I've hit a wall.

I've bought an ae85 with a 4age bigport. It has a motec m4 installed with electronic ignition. Not too sure on the details of the ignition but I'll chuck a couple of engine bay pics in as well.

The tacho doesn't work. I've pulled the dash cluster out and the board is fried where the tacho wires go. My gf's dad is an autosparky and helping me out. Basically what I want to know is if I buy a replacement cluster, can the tacho work? He said it very well may not due to the ignition changed so I wanna know if I'm wasting my money. In which case I'll just buy an aftermarket tacho. This has obviously been done previously and taken out with the wiring behind the dash/holes to mount it. But I'd much rather keep the standard tacho if possible. The wiring behind the dash cluster is getting a signal from the ignition setup.

Also, if it is possible with a new cluster, what needs doing to wire the standard tacho up?

Thanks for any advice and help