clutch won't disengage Options

[gbp808]

Hi All, my "roller" '75 914/4 2.0L was eventually able to fire up (yay!) but next problem seems to be that the clutch won't disengage. The car has been non-operational for many years, PO did not share what "broke" before non-use began. Currently she seems to cycle thru all gears when engine not running and clutch is depressed. Starting in neutral is fine but cannot get into any gears, grinding++. I tried bumping the starter in 2nd gear, with clutch depressed, a couple of times but plates did not disengage.
I tried light tapping thru the big hole on the inboard side of the starter, no help (I was not confident of what to tap and did not try very hard).

Looking at the clutch cable, there is some free play of the pedal but cable seems OK to brief inspection. Presumably since it cycles thru gears with clutch depressed and engine off, the cable is doing it's job correctly...? Therefore it must be a frozen clutch/pressure plate or throw-out bearing? If this is a correct assumption, does anyone have any suggestions, or is the next step to remove the transmission?

Many thanks!

[Artfrombama]

Start the car in gear (hopefully in a large open area) and with the clutch pedal depressed, apply on and off the accelerator until the clutch plate breaks free of the flywheel.

You can also rock the car back and forth in gear with the pedal depressed