Paul-
If you’re looking for a new home for your PSRU oil drain; I found it was really easy to drill through one of the engine mount holes on the plugs side for my oil return.  The existing stud hole sizes are just shy of the ¼ NPT we need and the holes are above the oil level.  I put my return into the bottom-rear hole (see picture).
 
This of course assumes you aren’t using the engine mount area for something strange…like your engine mount ;-)
 

Joe Hull
Cozy MkIV #991 (working on Engine & Electrical & Finishing)
http://www.maddyhome.com/canardpages/pages/JoeHull/index.html
 

Joe, are you sure about that? I think the opening just to the left (with the bolt head) is the water jacket drain.
Bulent

Yep.  I checked the distance from the bottom of the hole to the inside of the oil gallery and it was only about 3/16”.  Then I drilled out the hole while the oil pan was off (of course) and got a good clean hole through cast iron.

Joe