6 speed 6060?

Only thing that sucks is those use 2 things that need to be overcome to be swap friendly
Remote shifter with funky tailhousing
Bolt on yoke coupler for ifs

I picked up a Challenger TR6060 a few years ago for around 2K with clutch, bellhousing, and flywheel.

As listed above these are issues you have to contend with, a T56 magnum is an easier option however the TR6060 is do-able.

The remote shifter can be removed and you can bolt one of these in place:
http://www.core-shifters.com/servlet/the-596/Core--fdsh--Hurst-Shifter/Detail

You need to get a custom driveshaft made up which has an adapter plate which bolts to the 3 star flange:

http://i178.photobucket.com/albums/w268/BKB94/001-3.jpg

Also you will need to make up a custom cross-member.

Note there is no VSS sensor for an electric speedo. So you would have to use something like a hall effect magnet system which you put around your driveshaft and it measures the pulses.