'86 JD216 problem after changing both belts - PTO is engaged

[ooops]

I've change both in the past (with copy of JD manual). Usual space, etc. problems. Tractor on shop floor. This time went normal. I did steps prior to
adjust variator. Which I've done a couple times in the past. Turned key and starter turned enough to lock up at flywheel. Multiple times. No movement.
(Spark plug had been removed.)
I see nothing out of place, etc. Not enough leverage to make belts and motor rotate. Previously started easy/ran well except worn belts.
Last belt change early 2016. Battery shows 90% on charger. ??

 

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After fully charging battery and tracing all wiring, I tried again. Clicking sound came from PTO bracket hitting the "stop" pin on the block.
Keeping engine from rotating. PTO switch off. Switch on, same. Disconnect PTO lead, same. I haven't used PTO in years. No accessories attached.
Seat safety/neutral safety switches removed when I bought it in 2006. Any other devices I need to look for, or ?

 

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BTW - PTO spun freely when I replaced it after belts.