200R4 swap questions

At Wilcap. $575 plus shipping. www.wilcap.com/mopar.html

I am looking for a core 200R4 to take to my friends transmission shop and let him build it for me. I figure $300 for a used tranny and about a $1200 build and I am golden for near $2000. All I have to worry about now is electronics in the new tranny.
The electronics only need a 12 volt source to work and the a used tranny can be gotten from the junkyard. The Pick-a-part around charges $100 w/o core ($90 with core).
http://www.wilcap.com/downloads.html