Most of the info is on these forums http://vpuniverse.com/forums/forum/132-pin2dmd/

Its def a bit of mucking around, and maybe buying from pinballsp is a lot less hassle.  I bought the LED displays and power supply from China - you then have to cut the display backing panel up to the right dimensions, then make a frame to mount it all in your machine.

Wire the power supply up, and then purchase the boardset from the guy on vpuniverse.  This then has to be registered.

After that, you load the SD card with your type of machine (software available on links on vpuniverse), then as mentioned, set 4 colours for the 4 different shades displayed on a normal orange DMD.  If you were super keen, you could customise each frame in colour, but that is well beyond my ability or inclination!