You can add a 1/4 oz. of florescent UV dye to the oil to pinpoint the exact source, or simply spray foot powder onto the area. The foot powder works pretty darn good to indicated the oil trace. Another option is to use a smoke machine in the crankcase and watch to see where the smoke comes out.
No need for any more look for tricks. I can wipe and watch it seep out in that area between the head and block.
No pressurized oil at the front of the head.
The oil drain in each corner is just that, a drain. Most of the oil goes to the back due to engine angle on most cars.
Hard to believe the source of the leak has anything to do with the intake. First thing I would do is pull the valve cover and check head bolt torque.
You would think. Let me share my oil leak frustration. I had same oil leak. Used three different head gaskets and still leaked. I had the engine on a run in stand so it wasn't an awful job to swap out, but still major pain. I tried sealant around the drain, coating gaskets, non-hardening sealant, Hylomar, etc. I noticed that the leak would move up the more sealant I added to the drain. So one day I was in the office shooting the bull with another mopar guy and we started sketching the oil system on the board. We drew up the pressurized passages and then started playing what ifs. So I knew there is pressurized oil in the rocker shafts. And that the rocker shaft pedestals for the supply line had holes drilled to supply the shafts. What if the front stands were drilled too? Pressurized oil could get down to the head/block interface. So I removed all the pedestals. Sure enough 6 out of the ten had oil supply holes drilled. These were aftermarket stands and I do not know who made them as they came with my box of rocks. So I tapped the holes on the non supply pedestals and inserted a set screw with sealant. No more leaks. PS, I call my Hemi a box of rocks because it was a large crate of parts that couldn't have worked all together. I ended up replacing some large money parts to finally get a running engine. It was an ebay purchase of a freshly machined engine just needing assembly so I took my chances. And partially lost. I did recover most of the parts.
