Oil pressure question

[Project1970]

I just realized I'd never paid attention to exactly where my oil pressure gauge sits, especially when hot...all I do is make sure it's not at zero

I'm not having any problems, so I'm not worried, but I'm just wondering...whereabouts is a good area for that gauge? At about 650-700RPM (idle in gear with A/C on) the gauge is at the first 1/4 tick; upping it to about 1000-1100RPM brings it to half and it increases slower from there. I don't think it goes above the third mark, even to 5500RPM, but that gauge is the least of my worries then

Anyway...it's a somewhat tired 135,500mi 33-year-old 350 with 20w50 oil. Normal? High? Low? Surprised it's not squirting everywhere / seized?