After searching, I've found that the majority of turbos (rule of thumb) should not be fed any higher than 25 psi of oil pressure. Although, I've also heard that pressure is not the concern, but the amount of volume of oil is more important. I was thinking about installing an oil pressure gauge after the restrictor to ensure that my turbo would see the right amount of oil, however, if volume is the concern how can you monitor it? I'd like to have it dead-on the first time, rather than finding out after the turbo starts smoking or possibly putting the seals at risk.

 

In searching you will find that journal bearing turbos and ball bearings like different oil pressures, the latter liking lower pressures. There is plenty of info in the archives.