Currently I'm working on another controller - this one will take the engine coolant temp from the CAN data of the M57 ECU, and drive an emulated signal to feed into the BeCM and thus get the temperature gauge working correctly. It will also control my electric cooling fan. This avoids having an original P38 temperature gauge sender in a hose, and a fan switch. It will also have the capability to deal with the A/C demand/grant signals properly, so the engine can decide to cut off the A/C under heavy acceleration, overheating etc.
Few advantages - one, no need for two additional senders in hoses, two - I can choose the exact temperatures I want the fan to come on at, and exactly how the temperature gauge behaves. It will also have failsafes built in - so if the sensor on the engine fails, the gauge can show a fault condition, and run the fan constantly. Similarly, if there is a fault with the CAN data, or even a failure in my controller, the gauge can give a visual indication of this - I'll demo it all in a video some time.
After that, I need to look at the intercooler again. The exhaust downpipe really needs a better custom one making up too. A/C as mentioned needs pipework.
Other than that... I've actually been looking at the full nudge bar I've been repairing to go on again in the last week or so - just as a slight change of attack :)