Remove Drawtite #6001 pin

[swbouton]

Hello. I've got an old Drawtite #6001 5th wheel hitch in my truck. I need to be able to remove the head from the base so I can carry each assembly off the truck or back on. The problem is that I can't get the large pin to rotate so I can pull the linchpin. Any ideas?
The Pin:


The place opposite the pin:


The label on the base:

Moderator edit to re-size pictures to forum recommended limit of 640px maximum width.

[ACZL]

Good deal !!!!

[swbouton]

I took your advice and was successful. I gave it a 4th shot of WD-50. I belted it with a 5# sledge and twisted the **** out of it with a good vise grip.

I was reluctant to "get serious" with it until I read your message.

Thank you very much.

[ACZL]

Couple of choices:

1. Pry down the tab w/ a crow bar to rotate it so pin can be removed.
2. cut pin off w/ a grinding tool and file flush so it will come out other side.