To have oil gush out after such a short time, my thought is pressure build up in the oil pan. Has a critter plugged the oil pan vent? Might be worth a little investigation before pulling the oil pan.

There is another possible source for the oil I'd check before tearing too many things apart again.

I believe there is a plug in the rear end of the main oil gallery that is NOT a threaded plug.

If it's leaking, oil will be hitting the front side of the flywheel which will fling it everywhere.

You could pull the distributor, make a shaft with a screw driver type flat head (I ground a lag bolt head flat on both sides and trimmed it so to fit down the hole) you can put that on a drill. Put that down onto the oil pump groove that sets below the distributor. Run the drill and that will pump oil throughout the engine. I even put a rubber tube on the bolt so to not scratch the hole. That may be easier to work with than with a running engine. All that and with the help of a cell phone video, placed where you can't get an eye close to, you might be able record more specifically where the oil is coming from. 

Just an update.  Have not lost interest in the car but unfortunately life has gotten in the way momentarily.  Early summer my youngest bought his first car and he had to but an exhaust on it and a few other thing to get it to pass inspection.  My car blew a head gasket.  Replaced it with a truck that decided it wanted a new water pump.  And so our summer went with the weekends being tied up with required projects or trips to local car shows.  My oldest is now in college and between that and his job it takes most of his time.  Youngest is in his final year of high school and in sports.  On top of that we are re-doing the kitchen.  Needless to say the car 41 is temporarily on hold.  We are still doing little things hear and there but have to tackle the rear main before driving it again.  Was able to determine that was the issue.  

Wish we had more time but over the summer we were working on cars just not the 41.  Had to focus on the daily drivers.  We did do allot of cruising in the 87 Monte Carlo though.  Somehow we put close to 5000 miles on it in a summer.  I know my oldest took it several places also so it was enjoyed.  The car was not made to sit in the driveway.  

Once the kitchen is done we hope to get back to the 41.  Just a matter of having time.  

Just an update on what is going on.  I know I have not posted in some time.  We have been driving the 87 Monte Carlo but the 41 is still waiting to be repaired.  Finished the kitchen and started a deck.  

Youngest graduated high school this year and a week later left for the Army.  He is planning for that to be his career.  Oldest is enrolled in an accelerated year round collage program.  All of this has but a limit on long sections of time to work on anything.  We plan to fix the 41 and have all of the parts on hand ready to go.  My oldest has a few day break end of summer so hopefully we cand get to it then.  I do miss driving the vehicle but every time I see it I think of the times we had fixing it and riding in it.  Just a matter of time till it is on the road again.  Oldest says once all the house projects are done it is on the schedule again.  

Time stops for no one. It's called Life Happens.