Help needed with sb 318

OK, other than the alternator bracket, which still needs to be resolved, I think you have set me on the right path regarding the core plugs and dip stick.

Next question. I'm needing to replace all the gauges, none of which are working. Found an affordable 0-4000 rpm tach, which for this purpose, has an hour meter on it vs. mileage meter. But need the other gauges too. Any recommendations for an affordable, economic set? Since the run is at least 15 feet from engine to cockpit, thinking electrical units. Looked at Ultra Lite from Autometer, but they are a bit pricey for this use. Should that be 100 psi for the oil pressure?

And what engine oil? Thinking 10w-30 or 10w-40?