Carl, here is a site you can go to and get basically a repair manual for
free on your truck..

http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/0
a/2a/8e/0900823d800a2a8e.jsp

This covers just about any engine you could possibly have in the 87-93yr
range. I see the bolt on the diagrams that you are talking about, and there
should be an access hole, just large enough to be a Torx driver down in. I
have used this site many a times so that I dont have to buy tech manuals for
alot of different cars. You got lucky, they cover your truck. This all
usually comes straight out of a haynes manual.
Good Luck,
Pk

You know what?  I just did the same job about a year ago and I can't
remember the details of that torx to save my life.  The irritating thing is
that it seems you need a long, narrow torx socket because the space in there
is so narrow.

The only thing I do remember is that I was unable to get a torque wrench on
that one when I reinstalled the plenum, but that may have been a space
consideration since mine was in a van.

Best suggestion I have for you is call your Ford dealer and ask one of the
techs what size torx it is and what they suggest.  The techs I've talked to
have been pretty helpful on that stuff.

CJB

In article
<8%7Bf.5026$Hd4.589@newsread1.news.pas.earthlink.net>,

The bolt is a T-40 Torx.  Snap-On has a version with a 6.5" long
bit specifically for this job, part # FTXEL40E

Before the tool came out, we used to glue a T-40 1/4" hex bit
into a 1/4"X1/4" drive socket and get them that way.