#1
This is a used SH4 pickup. I am reading 8.7 to 8.03 on the multimeter.
on the Trem side the other TB4 is giving me 18+
What should be the right number?
#2
connect the white and red wires (if they are not) then see what the DC resistance is

If I remember right, it should be around 14
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#3
+1, you are probably using just half of the pickup. Connect two wires(don't know the color) to use full humbucker, or think about push-pull potentiometer, for coil split