Hello fellow SVX ers

I am going to swap the very low mileage auto from an Impreza RS into my svx including the rear diff, driveshaft (if the svx one wont work) and torque converter/flex plate.

Two questions I might need help with:

1) will the svx electronic switch attach to the imprezaRs plug?
and is it necessary?

2) can someone recommend a specific trans cooler or installation article because it seems the right time to install one: should this help preserve the box?

3) I understand Subaru introduced a new upgraded torque converter at the end of the model run: are these available for a reasonable price: anybody had any experience with retrofitting this unit?

Thanks for all the help so far
Richard