On my son's T25 the original fuel gauge has not worked for months and we are thinking of replacing with a Sport-Comp AM3316 gauge from VW Heritage. This gauge is rated at 33 to 240 ohms range and matches the VDO tank sender. I have a spare nearly new one and the multimeter shows its good and in range. We need to drop the tank anyway, which is centre mounted and easy to get at, as the repro balance pipe is too short and popped out the tank, and the earth wire from sender to chassis is crusty as shown on the endoscope. Accessing the original guage wiring behind the dash is a pain and the old pcb ribbon circuit is fragile and prone to breaking just by looking at it and a new one is £250 so understandably my son wants to leave well alone. As the tank is coming out we can do any wiring needed and presumably the new gauge is simpler and works at 12v.