oil pressure problems

[nobby]

I recently did my brakes on my vanagon only to drive it afterwards with a noisey lifter. I did have the wrong filter and oil but am now at a point where I put in an oil pressure gauge and changed the filter to mahle and the oil to 10-40w with 1/2 a can of Sea foam in the crankcase.
I started it up and the lifter seems to have freed itself but the gauge didn't work. I put a ground on the sending unit and now the needle raises itself off 0 barely. Now I'm having a beer so I don't smash anything!
My question is how common is this to happen, it ran fine before, no oil warning lights (though I did find on of them not hooked up... the one under the water pump pulley) and is there something I'm missing or do I have to replace the pump now! I am getting an oil warning light by the way.

[Wildthings]

Install a temporary mechanical gauge until you figure out what is going on.

[nobby]

ok will try that next