The valve body with the steel separator plate stamped 10225/1000041 is probably gold colored from a B&M Shift Improver kit. This plate might not be compatible with the TF-2 kit so you'd be better off to get an untouched VB.

For a '66 trans you would want a '66-70 VB but a '71-'73 will work.

Makco is a good source for quality rebuild parts at good prices.

http://www.bulkpart.com