May be able to save you a lot of time.

The Megasquirt guys have been working on a universal standalone solution. There are 2 versions of this. One using the GPIO board, which is a generic board with a ton of inputs and outputs.
http://www.msgpio.com/manuals/mshift/index.html

There is an old thread on the GPIO forums about the RE transmissions but it looks to be dead for now.

The MSExtra guys have a solution using the existing hardware of MS2 or Microsquirt.
http://www.msextra.com/doc/index.html#trans

Hope this might help..