I have a 270 inline six in my 57 GMC tow truck. It does not have an oil filter... It'll be easy enough to install a remote filter, however I'm not sure of the direction in which oil flows. There are two plugs on the block, #1 is towards the front of the block under the exhaust manifold and #2 in a located towards the rear of the block, a little high than #1. If I had to guess I would say that oil flows from #2 through the filter to #1... Thanks in advance for any help in this matter.

Allen A.