Looking for Source of an Oil Leak

[wutanec]

Hello,

I have been experiencing a sudden oil leak - a serious enough to wet the pan and drips to the transmission and cat. So I lease a lift to check out the common areas mentioned on the forum. I cleaned the bottom of the car thoroughly with a can of brake cleaner to see where the leak is coming from.

1. Oil Pan: looked dry and no more oil was leaking - I tightened the bolts anyways to make sure.
2. Oil Pressure Regulating Valve Cover Plate - looked dry, tightened the bottom bolt only as the top one was impossible to see or reach.
3. Header Stud - was not leaking, looked like the oil on the CAT is from oil deposit on the pan.
4. Oil Pressure Switch - looked pretty wet and leaked a little bit after I cleaned it.

So I am narrowing it down to the Oil pressure switch but it seems like there is a bigger pool more toward the front of the car - and drips down to the front of the leaf spring structure (picture attached). Could this pool start from the switch? or is there something else I should look for? Also, with my limited mechanical skill, I could not see any way to access a tool to remove the switch. is there any trick to remove this thing?

Thank you.