Using DS-MAP free software (
http://forums.ds-map.net/index.php)and an Ostrich and a logging cable, you can convert your DSM over to speed density.
The following method also works on 1G/2G DSM EPROM ECU's for DSM Link installs.
Note: Use the following guide at your own risk, I'm not responsible if you screw something up.
Get yourself to this stage, the stock chip that you need to remove is in the top right corner of the board pictured. Before you go any further, clean the bottom of the board around the chip pins with acetone/mineral spirits/mild solvent and a toothbrush, Mitsu ECU's have a coating on them that prevents you from getting a clean solder joint so make sure it's good and clean.
Use a Dremel or rotary tool to cut the pins off the chip. You'll want a cutoff wheel, some safety glasses and a steady hand to do it. Go slow, you don't need to apply much pressure to cut through the thin pins, and don't worry about cutting into the eprom. When you're done carefully pry the chip loose, it may still be stuck to the board with residue. You'll want to clean the board off with compressed air as well.
A lot of people will probably tell you this is a butcher method of removing an eprom and that you're better to desolder pins from the underside of the board and remove the chip intact. I've never had luck doing that and I've been using this method for a while now with no accidental damage. You're much less likely to rip out a trace (which often ruins a board) with this method.
Aftermath of Dremel attack.
So now you have 28 pins stuck in the board.
Take your soldering iron and heat the underside of the board and the pin at the same time. Best to do this with your good hand, as you'll need your other hand free at the same time for...
Use a small set of needle nose pliers to grip the pin from the other side while you use your soldering iron to melt the solder. Wiggle slowly to make sure it's loose, then pull it out. If you feel resistance, stop, and figure out why before you try and use brute force. All these pins should practically fall out once the solder is heated up.
Use copper Desoldering braid, or a desoldering gun/bulb and remove the access solder from all the holes. I often find it's easier to go over and fill every hole back up with fresh solder before doing this. Desoldering something that's half full is harder.
Put your 28 pin socket in the spot where the old chip was. Solder each pin, don't use too much solder or it will pool and make contact with other pins on the underside of the socket where you can't see it.
Put your ECU back together, plug your Ostrich into your socket and you're ready to go!