No, everything's good. I have a TKO 600. When I was idling at a light in town I heard a rattling/clanking kinda sound bouncing off the curb and sidewalk through the passenger door window. Took it to the garage here on the Island and put it up on their lift with the engine running. The mechanic had an electronic stethoscope which had headphones that cancelled outside noise but amplified noise through the stethoscope. We both listened and found the noise in the tranny area. That really bummed me out as the tranny was one of the few things I'd changed on the car that hadn't given me grief,
I went home and pulled the tranny, everything in the bellhousing was good. I took the shifter and top plate off, the input bearings and everything I could see looked good so I searched for more info before tearing down the gear box. Didn't get much help from Tremec or the dealer I bought the tranny from. I posted the snag on a few sites but no one could help me. One day I got a phone call from Modern Driveline, I believe his name was Bruce Couture. It was an unsolicited call, I never asked anyone at Modern Driveline and forgot to ask how he heard of my problem and how he got my number, but he called and straightened me out. He asked for all the specs on my build and to describe the snag. Told me the because TKO, unlike the Muncie, has very thin GM Synchromesh or Dexron III ATF and the camshaft grind is causing the lopey idle with torque applied and removed constantly the back lash clatter can be Heard many times more than that of a Muncie. He told me to reinstall the tranny and put it out of my mind. I asked him about putting 80/90 in the TKO, he said NO! It's made for sliding action of bevel gears, contains additives that corrode internal parts in the gearbox and the friction coefficient can cause shifting troubles. So I put it back together reinstalled it and I don't even notice it unless I'm idling it near a brick wall or concrete no-post.
D4VE67, sorry we are getting away from your original post and the long winded replies.