Checkcontrol has been available only on 6 cylinders
Wasn't just 6 pots that had the Check control.
M3s had it too;)
It's not impossible really, just a nice bit of work.
The washer bottle is an easy job,
Coolant level is easy enough too if you used an E36 rad,
Brake lights will require the associated wiring as mentioned.
Oil level could be made work too if you got an old M42 sump(In case you fuck it up)
Then put in an M20 oil sensor in to it by drillling out a hole for it and welding a threaded piece in to seal it again around the sensor.