Switch - oil pressure - thread size?

[Alan Drover]

The oil filter adapter has a thread in the mounting holes through which the bolts pass to screw in to the block which I reckon has been tapped into it because as it's a genuine Land Rover one it wouldn't have had the holes tapped and the thread is imperial as the engine is an imperial one and I kept the original mounting bolts.

[Discosport152]

Try 1/8" b.s.p.

[Alan Drover]

Checking my 110 parts list and I discovered that oil pressure switch PRC4044 has been superseded by PRC6387.