Oil Psi gauge hook up ?

[bl200sx]

Yeah, I got a electrical auto meter Oil presure Gauge for a black top S13 DET, I need to know how to get this working.
I need to get a presure line for the sending unit, that runs from the sending unit to somewhere on the engine, I need to know what size presure line will fit on the sending unit, and were do I tap in on the engine to get the oil presure for the sending unit.

Thanks,

Bruce

[the head]

best place to tap into is to remove the stock oil pressure sensor (right next to oil filter) get a 1/8" BSPT to 1/8" NPT adapter aviliable through autometer or through www.mcmastercarr.com then use a line to connect everything