Yo Daddio,
Welcome!
I believe the shaft seals may still be available at dealership.
Ask for them or the, Fuel Charging Gasket Kit; This kit contains the necessary replacement gaskets and “O” rings for fuel rail, injector, pressure regulator and throttle body service. - 80.6 MB pdf by Ford @
http://web.archive.org/web/20110704105317/http://www.fordinstallersupport.com/files/catalogs/fes200.pdf
site is very slow and did Not open for me after 5 minutes.
Need to check that the shaft is not worn out, if the shaft is okay, get brass sleeves to install in the TB or take the TB to a
machine shop and have them install the seals.
...
See
http://www.throttleshaftrepair.com
"Simple and Easy. No need for a drill press, special bits or complicated jigs - the Zako ATS throttle shaft repair kit lets you ream out the throttle body and install new bushings perfectly, every time!" Ask them if they have your year kit.
...
Here is an overview of "TB Shaft machining. $35;
Shaft is machined to a thinner profile to reduce turbulence. New low profile (flush with shaft) screws are installed. Not available by itslef at this price, only as part of TB boring service."
by
http://www.maxbore.com
AsK at local NAPA, ETC. And some of the old speed shops may have some.
1986 FORD BRONCO 5.0L 302cid V8 : Fuel/Air :
STANDARD MOTOR PRODUCTS 2006 Click for more information about this part
{Click Info Button for Alternate/OEM Part Numbers} Contents: Injector Seals, & Gaskets for IAC, TBI, Plenum, & EGR Valve
http://www.rockauto.com/info/154/2006photo%20primary__ra_p.jpg
$0.64
http://www.rockauto.com/m/mobilecatalog.php?carcode=1105917&parttype=6474
Cleaning Procedures as Shown in Idle Air Control (IAC) Sludge; Poor Idle TSB 91-25-07 for 85-92 Bronco & F Series & many others @
http://www.supermotors.net/registry/media/724437 by Ford by Stephen
Cleaning in an 86 5.0
Source: by Sixlitre (Malcolm H, Eddie Bauer) @
http://www.supermotors.org/clubs/superford/vehicles/registry/detail.php?id=4970&s=27143