Yes it will bolt to the XR2 transmission.
Yes, you can use the B6T engine management, but if you buy a real BPT w/ BP26 ECU, it's better to use that.
You will have to notch the passenger framerail to allow clearance for the belts/pulleys
There's a whole bunch of little things that needs to be changed/worked around, not a big deal stuff though -
-Throttle cable on the BP TB
-Fuel lines
-Intake routing
-Vacuum lines
etc etc...