Generation III External Engine - oil pressure problems, opsu?

the oil pressure gauge has always acted funky, shaking around, and showing weird readings. now it goes up till like 5k rpm then till it shifts is at about 45 psi? what am i missing? opsu problem? im going to try and see if anyone local has a manual gauge i can plug in to see if its the opsu or not.

heres a video of it

https://www.youtube.com/watch?v=rpD2ych34Oo

Now it's not doing it anymore, so more then likely gauge or opsu, damn you gm

And sticking randomly, either when I had the cluster of I pushed it on accident and it's to tight or it's the gauge/opsu