seriously the best manual trans 5 spd will be the Passon , Tremec is problematic , my next choice would be a Viper T56 Magnum but you will have to rework the floor to fit it .
Passon is great to deal with & can supply a complete kit .
Brewers can also supply everything except the 855 trans & is great to deal with also .
STAY AWAY from Keisler , seriously !!
Welcome BTW , What color is the R/T SE ?