Often shows up as a pile of shiny metal shavings directly below the filter...it's bearing material from the thrust washers in the converter.

I have a Gearvendors off the back of a 700R4 that I'd like to get a 727 adapter made for.

You can't even talk to those people. Over $600 for their adapter and they will NOT sell it to me unless I return the 700R4 housing.

Kevin

I picked up a used GV unit from the salvage yard where I used to live. It was behind a 460 in an RV. I exchanged the adaptor and had them check out the od unit before I used it. Turned out the old one was on its last legs. By the time all was exchanged, they do the od units on an exchange too so you can get a fresh one, got other pieces to go with it[ minus electronics] I was within a couple hundred bucks of buying new outright. Something to think about since you are a pretty fair swim from getting parts easy.

i did a cost comparison between beefing up an A518, and a gearvendors unit, and taking the converter out of the equation [every application will be different, and a good converter isn't cheap], the A518 rebuild, plus the UltraBell needed to attach the transmission to my big block, it was cheaper to go this route and the overall length was a bunch shorter than the 727 plus the gearvendors unit.
i too, was put off that gearvendors wanted the "????" adapter back before they would "sell" you the one needed for your application.

The overall length can be mitigated by using a motorhome or truck divorced transfer case 4x4 trans. I think they have a "shorty" kit that uses a married 4x4 trans for a close to stock overall length.

Kevin

i have used the transmission for the divorced transfer case 4x4's before.
the ones i have done, and the two on the shelf, are from small blocks.
i used the tail shaft and housing, plus related parts, in a big block case, and that worked good.
in fact, i was going to use one of those transmissions plus a gearvendors unit in my 33 dodge humpback panel truck [the "eternal project"] until i found out gearvendors wouldn't sell you the adapter housing and the splined coupler unless you sent in those parts PLUS the money for the parts i needed to couple a chevy unit to my transmission ! [i had a deal going on a used chevy piece]
now why is THAT necessary ? what do they do with MY parts ? rip off someone else that needs a chevy coupler and housing adapter ?
not on MY dime !