Fuel tank outlet removal problem

[lrg355]

I had about 3/4 tank full of old 2 stroke mix in the tank of my project boat.  Removed the sending unit to have a peek inside.  Couldn't see much except 3/4 full tank.  Decided to siphon it out. Put a hose on the fitting, ran it thru transom drain hole to a 5 gal can.  Had a few cans ready.  Tank is 24 gal.  Tried to siphon it, no luck plugged tight.  Tried to blow in, no luck, plugged tight.  Put the hose in the sending unit hole and siphoned about 15 gal.  So the pickup tube is blocked or has some type of valve or filter that is blocked.  Ok, now try to take out pickup tube and elbow fitting on top. No luck again.  Time to look at YouTube to see how this disassembles.  It shows that the top elbow fitting should screw out of the " sleeve" fitting on the tank.  

Cleaned it up, put on AeroKroil penetrating fluid. Waited a few hours.  Held the 1 1/4 nut and tried to unscrew elbow fitting. No luck, stressing it to the point of breaking something so I now hesitated.  Does anybody have any experience with this fitting and pickup tube removal?   This is a poly tank made by Kracor.  This is on a 1985 Sea Nymph 195.

[lrg355]