No use to try bleeding the system, I bleed mine by driving it.
The master cylinder is the high point in the clutch system, as you drive any air in the system will work it's self to the master cylinder.

When you say it sticks.
Is what you are seeing is the pedal returns about 1/2 way up, and then just stays there?

My guess is one of two things.
There is an assist spring that helps you hold the pedal down.

Either the firewall is cracked, and letting the master cylinder move away from the pedal arm enough that the assist spring is holding the pedal down or the master cylinder is bypassing fluid internally which then lets the assist spring hold the pedal down.

Have someone push the clutch to the floor while you watch the master cylinder.
If it moves more than a very tiny amount, you have cracks in the firewall around the master cylinder.
Ford used to have a mend plate to fix this, but it may be discontinued by now.
I fixed mine with a 3/16" thick steel plate about 4" square.
Drill a hole for the master cylinder bolts and the piston rod, un bolt it and unhook the rod.
Slide the plate over the rod from inside the cab, reinstall the nuts and hook up the rod.

If the master cylinder is bypassing fluid internally, you need a new master cylinder.