In a cooperative effort between Cherrier and ETK, Cherrier introduced the FCV, and not long after quietly started slipping in automatic transmissions with help from ETK, the first of which was a 10-speed, codenamed the 10FW90. Little was known about it at first, but after people got their hands on the first unit and dug into it, it was a surprise to many to see it was a joint effort between the two companies, seeing as ETK killed off their own 10 speed late in development due to worries that it would cannibalize the long-established king, their 8 speed. More interesting was the fact that even more transmissions started finding their way into the FCV.
So ultimately there are quite a few converter choices, which I had to do both for driveability sake as well as for shifting. Obviously the starting trans is the 10 speed, but along the way expect to see a 7 speed as well as a 5 speed make their way in.
NOTE: You will have to choose a torque converter after selecting the transmission, it doesn't automatically put one in. I would also opt for the 3.389 diff with the 10-speed and 7-speed units as that's what they were developed with.
7-speed and 10-speed converter options
Automatic Transmissions for Cherrier FCV 1.2.3
Automatic for more zoomies