C4 stuck in park

I have a race built JPT C4 with a few mods a trans guy did. Anyway, it is a reverse pattern manual VB. I have a B&M Pro Ratchet shifter. I put on a new cable, adjusted it, everything was PERFECT for about 20 runs (high 10's).
I pulled up next to my traier, put it in park, shut it off. Nothing unsuall. When I went to make the next run after my cool down, it would not come out of park. I unhooked the cable from the trans linkage. The shifter and cable are fine.
The lever was stuck. I started pulling/ wiggling/ prying/ soft hits with a hammer and it was free. I hooked the cable back up. Shifted through all gears, fine. Put it in park and it stuck again. Repeat of above.

What could cause it to suddenly stick in park? The trans was just gone thru by a pro before the install. All was fine inside and I use Amsoil series 2000 racing synthetic fluid.

What can I do to check things?

Dan

Pull the tailshaft. Doesn't happen very often but I broke a spring on the parking pall & it dropped the arm into the park gear. There might be other problems such as the brake solonoid is stuck, but I doubt that & the T-shaft is easy to pull[img]/phpBB/images/smiles/icon_confused.gif[/img]
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