You can use Autometer part #17303, 17305 or 17311 these are the 2 -1/16" style the smaller ones and stick them with a good adhesive first then use body filler to blend it in and sand it till smooth water sand and paint to match.If you are running a performance engine the guages are a cheap insurance of the crucial engine functions so you can monitor what is going on before it is too late .....better safe than sorry.
Still working on the car Smooooth fabbing the mounting for the turbos pics this week coming

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