Low Oil Pressure Reading 75 1.8

[Ray Morgan]

My idiot light keeps coming on. At idle (900 rpms) to 1800 rpms the light will remain on. I have replaced my oil pressure sending unit.

I am also taken a true oil pressure reading with a compression guage -- 9 lbs at idle.

Unfortunately, inside the hole where the sending unit sits, the threads are slightly stripped, so the compression guage didn't fit quite right.

Any suggestions for a solution to the low oil pressure reading? Any idea how to thicken the shaft of the sending unit? Will a sealant work on something like this?