51Greenmachine,

No, that hole was already there and I think it might have come that way from the factory. But, I do not know that for sure - I bought the engine at a salvage yard in 1972. The engine came out of a school bus and the oil filter was the GM full-flow large canister (quite an impressive unit).

If you have the brass fitting and it has no hole, it should be fairly easy to tap a hole (you might be able to see that the hole in mine needed a reducer for the line to my '54 gauge).

In the photo below, it is not possible to see the oil pressure line but the diagram shows the direction of flow of oil. I my first post above, I said the oil pressure line was on the inlet side - I was wrong, it is on the outlet side of the filter (inlet side of the engine).

Also, note the stand-off tube/pipes on the oil lines - the one on the left is easy to see.

[img]http://ares.cs.siena.edu/~lederman/truck/Documents/fullflowsetup.JPG[/img]

Tim