My car started life as a na auto. Previous owner swapped in a tt but left the na auto. It went out on me so I bought a jdm tt auto, torque converter and flexplate & swapped it in. Plugged in the harnesses, & flipped the transmission mount around. Slapped the front half of a tt auto driveshaft to my na rear & was driving again. Sounds super easy but it was like 20 hours of work lol. But it really wasn't that bad. The tt auto is much beefier than the na.