Whelp, chocked the wheels, and put a floor jack under the left rear axle area.
Started it and with the hand throttle pulled out and revving at approx. 2500 rpm's, and with the clutch pushed in, I slammed on the brakes hard, many times.
Engine slowed down to almost a stall,each time. Took my foot off the brakes, let the rpm's climb again and then slammed on the brakes hard again, many times.
I got the smell of hot brake lining, but unfortunately the clutch did not break free.
I wonder if there are any other suggestions, or if it will need to come apart?

Mike