Had to do the same thing to my 86 four years back
Chances are good the huge cast iron air pump bracket is still there holding up your alternator. All you'll need for that is a new air pump from Cardone ($65 CDN) and a long bolt and small bracket from an 86 only F-150 or Bronco.
Next lay across your engine with you chest on the upper intake and feel behind the lower intake. You're feeling for the pipe that crosses between the heads and mounts the 4 way diverter valve in it's center, between the heads.
All that stuff was missing and broken on mine, so I spent $10 at a junkyard and scored it all off an 89 F-150 with an EFI'd 302.
Feel downward, from the diverter valve, for the connecting air pipe that'll go from there to the cat. Probably ain't there, but you can buy a cheap kit that will get you from the diverter valve to the nipple on the cat using copper tubing(@$12);
Lastly, one stop shopping for your replacement cat;
http://www.fullsizebronco.com/forum/showthread.php?t=28101&highlight=streetgang+catco
Streetgang hissef' pioneered the first install of this. When you consider what a shop will charge you to supply, cut and weld in another cat, it would cost less to buy this and bolt it on yersef'.
Good luck, mine never did pass the third part of test, but they was forced to give me a conditional pass each year until I became exempt forever (this year she's 20 years old!)
I'm thinking of celebrating by pouring a can of Seafoam into her 5 minutes before I pull into the parking lot to get my tags.
I'll leave her running while I go into get the tags and by the time I come out you won't be able to see across the parking lot !
I'll exclaim to the coughing, frowning NIMBYs and eco-nazis, with a tear in my eye; "I'm exempt, hallelujah, I'm exempt !"
Sixlitre
