Oil cooler always a great idea!! I am currently tapping one into my 4AGZE. I have machined up a block which sits where the oil filter attatches to the block, then i am running lines out to a remote oil filter mount, then running it through the cooler and back into the first block which is attatched to the sump. by doing it this way i am utilising the oil pump pressure into the filter, and also getting filtered oil through the core, so it avoids blockage.
Unfortunately i don't know how well if at all this will work, but it should. I need it cause i have a turbo 4agze in the build.