Can't remove quick release plate pivot screw. Ideas?

I'm upgrading to a E3Dv6 hot end on my son's R1+.

Printed a new quick release plate off Thingiverse, but I can't get the old plastic quick release plate off.

The screw that allows the plate to pivot won't budge and I'm afraid I'll strip out the phillips head.

Is it held on with Loctite?

I'm thinking of touching my solder iron tip to the threaded end of the screw to get it to turn.

Any ideas before I try that?

 

It's screwed into a metal hex nut that is sunk into a hex shaped pocket on the plastic assembly that holds the large gear. Feels like I'm about the strip the head. If/when I get it off I'm going to replace the screw with a hex cap screw if clearance allows.

 

OK got it out. I applied about 45 seconds of heat to the threaded end of the screw using my Weller solder station. Not a nylon nut after all. It's a regular steel nut with about 4 threads covered in blue Loctite. Will reassemble with new screw & nut, and use a hex cap screw if clearance allows.