The rev counter/fuel display is made by VDO, it seems to be based on their Ocean Link Range. Installation instructions are here: http://www.mechanikadc.cz/wp-content/uploads/2014/05/MI-Dzm-CAN-Master-EasyLink-GB.pdf and whilst you can select fuel level display and calibrate it from a button on the front of gauge it would unfortunately seem that the M3W version is probably preprogrammed and calibrated to suit the 240mm tube sender.
Seems NOT, because it reads more accurately.
On another note, anybody understand ( maybe OP Richard?) why the word "rack" is in the thread title?
