Spidermo

I have just found out that my motor is locked. I have a 86 N/A. I'm looking to turn this car in to a autocross toy. I would like to get some pointers on what mite be my best move. I'm already missing the rear diff but I have a good tranny and axles. I have a line on a TII motor and ecu and have heard that they can be setup to work with a N/A driveline. I also am thinking of going to a 13btt and trans. i know that you all know RX's alot better then myself. So what would be my best bet for a good autocross car.

Please HELP!!!
Spidermo