Dash doesn't work Pleeeease help

[si.]

Ok so the clocks in my car have pretty much never worked properly and its on the extensive to-do list while she's off the road for the winter

This has also lead to me running out of fuel twice and having to be recovered which is getting annoying/expensive/embarrassing/etc

It's originally a 316 and everything on the dash still is but the car has an m20b25 so the fuel pump setup has been changed (read on as to why this might be relevant)

So my standard clocks.....
I get all the lights on ignition so batt/oil/high beam/indicators etc they all work
My Rev gauge works although it reads 1.5 times higher due to it being for a 4cyl car
My fuel gauge does nothing doesn't even move (could this be due to the new pump setup which is basically standard external 323 setup)
My temp gauge shoots straight up to the red even if the engine is stone cold, but once the car is started after a short while it drops to stone cold and stays there but before it does that it will fluctuate slightly when you blip the throttle which is very weird
My clock also works
My speedo doesn't have a drive due to the e30 gearbox but I'm not bothered about this

While at Shark Nose this year I purchased a set of 6cyl clocks and Ben fitted them at the campsite that night while I was cooking dinner lol
These worked quite well to begin with no speedo (again not bothered) but the Rev gauge lights etc where fine but I still had no temp and no fuel gauge
After about 40miles of driving they just went dead.....completely, the only thing that now works on them is the battery light on startup

I have just plugged my original set back in and fired up the engine and they still work exactly the same as before

I'm desperate to get the fuel and temp gauges working but don't know where to start I'm happy to swap the Rev counter into my original clocks or just make the 6cyl clocks work

As a side note my headlight switch is a bit wonky as well the dimmer switch doesn't work very well and most of the time I have no dash lights at all, it has to be set just right but if Ihit a bump that might knock it a fraction and everything goes off

Please help its a real pain just not knowing if the car has ever been hot and guessing how much fuel I do or don't have

Cheers
Si.

[Jeroen]

Looks like a mess indeed! I think you just have the wiring mixed up using the wrong signals. I'd start by checking wiring, no reason why the fuel level sender would do something different as long as its still in there. Temp sender: depends if its still in the thermostat housing but normally it should be on any M20, perhaps you need to switch back to the old sender as it produces a different signal. Think your messed up wiring blew the 6 cil clocks you fitted.

And light switch, common wear on the dimmer, just replace the entire switch.