When you ground the self test jumper and turn the ignition to the on position, you enable the computer to post codes of malfunctioning sensors. I would plug in and ground the wire, turn the ignition on (without starting the car) and read the codes. (instructions located here:
http://www.mx6.com/forums/showthread.php?s=&threadid=70310&highlight=cel+codes )
Replace or repair any malfunctioniong parts, switches, sensors, ect. as indicated by the fault codes.
Then, place the number one cylinder at top dead center (TDC can be found two ways: take spark plugs out, shine light in hole number one {nearest the timing belt}, turn engine over until piston is seen moving up, then down. Or, take off the lower timing belt cover and position the crank pully indicator mark to coincide with the indicator mark on the block) Then, if necesarry, loosten the timing belt tensioner and place the cam at TDC. (this is done by aligning the indicator marks on the top of the head with the arrow near the number 1 on the cam gear.) If timing belt is moved, hand crank the engine over 2 revolutions with a 21 (or 22mm, I can't remember) socket turning the crank pulley. Doing this properly tensions the belt, and you can then tighten the belt tensioner pulley. (if this is not done, the belt will just jump around on you)
Step 3: (with everything located at TDC) Assuming the dist. is in the correct location, take the cap off the dist. and place the rotor to point at number one. (this is indicated on the cap itself, or on my 89 and 90 GT's it's the post on the cap located closest to the intake tube attatched to the air flow meter.
When the dist. is positioned, attatch the plug wires in this order: (this is IMPORTANT as I have found the Haynes manual to be hard to understand and/or inncorrect) Begin at the post indicated with a number 1, going clockwise hook up the rest of the wires in this order: 1-2-4-3. {if you were to look at either of my cars from the drivers side fender number 3 would be on "top", 1 to the right, 2 on the "bottom", and 4 to the left or front of the vehicle}
Once you have all known parts in working order, and everything postitioned correctly, the car should at least run. though it may run rather rough! Turn the car off. Ground the self test jumper to dissable the computers' electronic advancement of the dist. Start the car, and use the timing light to set the timing at 9 degrees before top dead center (BTDC) (you may want to use a paint pen or even white-out to highlight the mark on the crank pulley)
I appologize if you are already aware of all this, but it is good reference. And since I fought my car last week for 3 evenings, only to start at step one on the fourth night. I thought I would simply advise you to begin at step one now. At least you'll know it's right!
-Britt-