I attempted to replace my fuel injectors and replace all the seals in my fuel rails today and had nothing but trouble. Mostly my own fault for thinking it would be relatively straight forward to get access to the fuel rails. I eventually I gave up because of a single bolt holding the intake runners because I don't seem to have any tool capable of accessing it, a normal torx wrench doesn't have enough space to rotate to loosen it and all the torx bit sockets i have are way too huge to fit in the small space I have.
Its the farthest back bolt on the bottom side of the driver side intake runner inside the red circle).
Any advice to get at this thing? Buy a different tool? Make a tool? Remove the part in the blue circle and remove the cold start injector?

 

Those bolts go from the inside out. Remove the plenum bolts and remove the plenum and these inside bolts will be accessible. Unless I’m totally misunderstanding your description. If so my apologies.

 

I did all my injectors on my 89 two years ago, had to run out to purchase this set of torx wrenches, a lifesaver.
A couple bolts I used the straight end with a 1/2" wrench on the curved side for more pork/torque 😂

 

I have always removed the valve cover to get easier acess to the bottom bolts. Little more work involved though.

 

You need a long shaft socket, one like this one I got from Mac tool 30 years ago but they are available on Amazon for $10 but I wouldn't expect to get 30 years out of it I certainly snapped a few doing the same job your on now.

 

I just use a long wobble extension and torx socket. Not too bad after to remove the brake booster fittings. Just takes a little patience.

When putting back together hand start all bolts...they like to cross thread.

 

Take a 5/8" wrench and remove that brake booster vacuum line, it makes it easy peasy. It only takes a minute or 2. It is easier to use (quality) 1/4 drive for this and a swivel with long extension. With the booster line out of the way you can get a straight angle on it. I tape all my mid quality drives so they don't pull off. And as @Ray Quayle stated there is a bolt on the inside that screws into the runner (second image).
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