On each of my mTDI vanagons, I installed the mk2 glow plug relay and wired it up just like the stock diesel vanagon. On my AHU, I used the stock diesel vanagon aluminum coolant flanges with the stock diesel vanagon temp senders for glow plugs and gauge. I had to modify the bypass hose, tho, as the angle is different when the flange is mounted to the center of the AHU head. If yours was originally a gasser, you can get the relay plate and fusible link from VW. You can wire the glow plug light to the OXS circuit of the cluster.