I replaced all my old 2” VDO black face gauges with new VDO Royale white face ones. The originals were made in Germany and the new ones I suspect are made in China but as I wanted white face I had little choice in the price range.
I too had 60-80 psi oil readings with the new electrical gauge. It was suggested on this forum to test the readings with a mechanical gauge. Readings were identical
WRT the temperature gauge try grounding the wire at the sender with the ignition switch on, no need to start it, you should get a full sweep of the indicator needle on the gauge. If not then the gauge may be defective
For speedos and tachs some models have adjustment screws on the sides of the casings. Check installation manuals or post the make/model and someone on the forum may have some experience with them and be able to assist
David B Dixon
Port Perry ON CA
Sabine