Buzzin Half Dozen

The guy who now owns mike Jeffries buzzin car is among those telling me to downgrade to a 904.
It was included in that pile that I hauled home from GA and I was told it was a good "core". The TC has been sitting next to it long enough to get rusty, and when I loaded it I wound up wearing about 1/2 of the ATF that was in the pan.
I'm 98% sure that my 727 has ring gear tooth issues, will need a converter when I swap the engine, this 904 will also need a converter. The 727 works great otherwise, fluid is clean.
I wanted to buy a Tork master converter for the 727 as I found one nearby, new in box for a great price until I ran the number on my 727 and found out it's a lockup version. Crap. I ain't sure whether the 904 is or isn't. If I DID run the "nasty 904" I'd definitely build it up before it went in.... But probably won't.