Oil pressure gauge 58 pu

[luckylynn]

I installed an early 283 in my 58 apache. I made the mistake of thinking the block would be like the mid '70s block I pulled out, so didn’t eyeball it enough before I stuck it in. Can't find where to connect my oil pressure gage. The hole above the filter looks plugged and unthreaded. Don't see it back by the distributor / atmospheric crankcase vent. Don’t see oil spewing out when I run it. I'm running the '70 intake because I don't have the early carb. Anyone have a picture to show me where to look?