These are the parts to convert a MS2 to MS3. Basically it's a daughter card swap which is the same deal as converting a MS 1 to a MS2. MS3 takes a taller case. Got these jewels from Diyautotune
MS2 surgery. The red jumper is for knock input and goes to a user prototype area on the board, it should function the same with MS3.
MS 3 daughter card installed.
MS3 has serial and usb interfaces. There is a slot for a memory card for data logging. Didn't get a MS3X card as they are not widely available yet. MS3X is the real meat and attaches to the other end of the case and has ribbon cables to the MS3 daughter card.. Sequential fuel is what I want out of it.
MS3 requires Tuner Studio software. It's no cost like Megatune. You have to buy a license for the autotune and datalogging parts if you want that. It's reasonable. Here is a screenshot of demo mode. I think I like it!