this adapter is probably only 25ish years old, I believe it came off a gmt400. Yeah I could maybe fish the spring out of the 3/8" npt plugged hole and stretch it, reinstall.
Did some more research. Worrying about nothing lol. The bypass is a differential valve. There is oil pressure on either side of it. It only opens if the filter is overly restrictive as that valve is both before and after filtering occurs.
So while it may be bypassing at all times to a degree, cold/thick engine oil and oil pump regulator failure (super high pressure) are about the only times the bypass is likely important.


. Shift into 2 wheel hi and just the normal vibration.