mass air conversion?

The only harness that will work on your 88 is and 89 engine harness. It just plugs right in.

You can buy the kit and convert you 88 harness to maf pretty easy.

Here is a kit from jegs with all the instructions with it.

http://www.jegs.com/p/Granatelli/750880/10002/-1/10439

$81 for a wiring harness and some splices?! that's crazy, go to a junk yard and clip the harness connector from almost any early/mid ninties ford vehicle ( just gotta make sure it's an oval plug, not rectangle), get some hook up wire from any radioshack or car parts store, and make your own harness for about $12. and also, while you're at the junk yard, cut off and buy the main harness connector where it plugs into the eec from any 80's ford car so you can get the EEC-IV terminals so you can plug the wires for the MAF meter into the EEC connector on your car. these are the terminals im talking about....

thats what i did and all my stuff works flawlessly. i even did the VSS and fuel pump monitor signal splice. here's all the instructions you need.

http://www.stangnet.com/tech/maf/massairconversion.html

oh yeah, and you can use either an A9L or A9P eec.

good luck!