You are absolutely correct about gauge overkill. It's been a dream of mine for a long time to have a cockpit with a full suite of gauges. It is certainly not warranted, especially on this understressed piece of 42 year old Swedish iron, but I think I'm going to jump off the edge and do it. The numbers that I have for the transmission and differential are about 120*F, running synthetic lube in both, so that may take a little time to track down a gauge that operates in that range. I guess another option would be digital gauges, but I'm not much of a fan of that look. Thanks to everyone who has responded here so far, it is much appreciated!