There is a company in New Mexico that can take the Veglia water temperature and oil pressure gauge and convert them over to Stewart Warner internals and use Stewart Warner sending units. A friend of mine had this done with his two gauges on his Pantera and it worked great. I know that isn't the question that you are asking, but I believe it is a better solution then trying to compensate for a gauge/sending unit mismatch. Your problem with the gauge pegging out could be an issue with the wire from the sending unit grounding out somewhere. I don't have any experience with this gauge compensator, but Pantera Electronics makes some very good products.
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