manual transmission conversion?

[retorq]

Get yourself a manual valve body and row your own gears.

 

[992dr]

^^^WORD^^^
OR, Tremec is the only way to go if you're going to go the manual tranny route.
Seriously, how did you blow two trannys? One within 4 days while breaking it in?
Sounds like they were built very well or you just beat the snot out of your truck.

Did you contact the builders for any warranty services?

 

[retorq]

I bet the one that went in 4 days had the cooler hooked up wrong or it was plugged and it super heated the fluid ... That is the only way I can think of killing a fresh tranny that quick.