Replace it with a hose tail then fit a short length of airline then a lever operated ball valve, this will allow the tank to be drained without having to grovel on the floor to get at it.
It was nothing special- through Amazon,240V AC to 12V DC power supply, a brilliant bit of service, It came in an Air Mail envelope, my previous order Via E bay came via Switzerland and took about 6 weeks.
i just got a compressor myself
opened the valve............it blocked.............took the valve out 1/2 bsp...............it blocked.............
i then took the 2" plug out of the end and then using a wet/dry vac and a bit of old hose pipe cleaned out all the crud from the tank