Thanks for the timely response, Bertsmobile.
Yes, I do have a vision problem, called 'macular degeneration'. And that was my first ever post on this forum using this provided format. I was still shocked at the final type size myself and will adjust accordingly.
It was deck being tilted that caused me not to be able to turn blades from beneath. Just recalled that yesterday while working on deck.
With deck down, blades do turn freely now and I can feel the drag of the shaft turning as I move the new blades I installed. So my 'brake' must not work because I have new PTO belts. But I'll get my lovely wife to watch the PTO and see if the belts are slipping as I move the blades today.
Engine WILL NOT quit when I get out of seat with PTO 'OFF' and control levers out, whether brake set or not. Engine WILL QUIT if PTO is on and I get 'my bum' out of seat. So the deadman switch appears to work.
Factory owner's manual just arrived in yesterday's mail and I'll be into that later today, after I drain radiator/block and do a flush/refill of coolant and the above mentioned inspection for belt slippage.