Oil pressure gauge

Whoever had my 1973 Duster before me installed a tiny oil pressure gauge in the instrument cluster, they fitted it into that round factory hole below the fuel gauge that I think would normally have an idiot light or something in it. It works but it's not stock, so out it comes. I have another instrument cluster I am rebuilding now.

I'd like to put an AutoMeter oil pressure gauge under the dash, all the ones I see are over 2" in diameter. I'm sure they'd work fine, but I'd prefer something smaller to not get in the way.