So lets get started, first off you will need the daughterboard/and header. a soldering iron, de-soldering iron or pump, and solder and a hammer drill.

First remove the holder from the ecu. I like to remove the ecu+holder from the car, it just seems easiest that way for me. Next remove the top and bottom of the ecu. This is what you need the drill with the "hammer" setting. Nissan glues the damn screws in and they're really soft, so if you use a screwdriver you'll end up stripping about every other screw. FYI if you do strip them use a 1/8th drill bit to drill them out. I haven't stripped any since moving to the hammer drill method, way cool.

Okay, so now you should have both covers from the ecu off.  I've circled the header position at the top where you need to remove the old solder and add your new header.



...and a close-up of the header
The jumper is on the back of the board. Its not like a PC jumper, its actually soldered in place. Its in the position marked 'CJ1' and right next to it you'll see a spot marked 'CJ2'. You need to move the jumper from CJ1 to CJ2(note: location of the jumper may very on ecu's

       


But lets start with the header. First there is a sealant on the board you need to remove. I gently wash it with acetone then rub away the sealant. Be sure to get both sides and the jumper in both positions too. Make sure the acetone is dry before the solder (duh!).


Now use the solder sucker and remove the old solder. Usually most will come out, but some holes are really stubborn, like the ones below. On these holes add new solder until it makes a nice bubble, then suck it out. Get all the holes nice and clean.


...ready to add the header (oh so clean!):


Now just solder the header into place.
 

Now lets move to the jumper. If you've got a smt solder tool (they look like a pair of tweezers) this is easy. If not, use two irons, one on each side, and gently pry up the little sucker. Don't worry if you destroy it, replacelents are cheap or a little bit of wire will work in a jiffy. Its glued to the board so it can be a b*tch to get loose sometimes. Remove the excess solder first with your solder sucker then pry away. .


Now you just insert your daughter board and your done, right?



...and heres it completed (ok, so this is an older prototype). That board isn't going anywhere, its in there really tight!


Put top back on and install in your car

Enjoy