Mart, the runners each have a "hidden bolt" that enters from the rear (i.e. from "inside" the plenum area. Once you know where they are you';ll never forget them (I've just done this job twice on my car and I agree it is HORRIFIC - one of the worst jobs I've ever done on a car, nearly made me sell my vette!)
One of these bolts is accessible by using a long extension from the passenger side and sliding it by the fuel pressure regulator while the other side is right near the thermostat housing.
If you're having a hard time getting to the lower bolts it helps greatly to lift the fuel rails a bit to gain access to these bolts. After undoing the 4 10mm bolts that secure the rails and the 2 fuel lines at the front of the manifold, make sure you remove the "bar" that runs between the fuel rails near the front of the rails. Then you can lift the rails, best to remove them by using gentle but firm pressure on both rails at the same time to lift them.
First time I did this job it took me days as I couldn't work out what order to remove parts in, - it truly seemed an impossible job!
Second time (I still had the oil leak I suspected was from the manifold so decided to do the job again!) I had everything removed right down to the intake in less than an hour! Dont you love a job that's fresh in your mind?
One tip that may sound obvious - make absolutely sure you clean the intake and head surfaces of every last trace of old gasket material, follow the gasket maker's directions using a real quality gasket - I would only use FelPro - nothing else, Callaway recommended FelPro too, and make sure you use RTV on the gasket where specified and a GENEROUS bead (at least 3/8") of quality RTV at the front and rear of the manifold where it meets the block. If you but the FelPro kit they supply RTV but there just isn't enough to seal the front and back. I bought a new (larger) tube and used plenty.
Otherwise you'll be doing that again like I did and swearing all the time you're doing it (like I was!)
Good thing is, once the manifold is out those busted bolts should be easy to drill out and re-tap.
Like you I couldn't believe how difficult this job was and how inaccessible the bolts were.
While you're at it check the oil pressure sender and switch at the rer of the block are'nt leaking My MAJOR oil leak was from a leaky sender and these parts are much more accessible when the manifold and distributor are out of the way. For insurance, while you have the chance and access, I'd get a new oil prssure sender (they are known to fail and when they do they can shut you down, after the embarassment of oil leaking onto your exhaust and smoking you out!) and remove the "hexagonal extensions" the sender and oil presure switch bolt onto, cleaning the threads and using teflon tape to seal the threads.
Access to these parts is very difficult with the manifold and distributor in place - there's no room for a spanner and you need a VERY deep and massive socket for removal.
Had to place this large reply to try and help someone - I can't get this horrendous job out of my mind!
And in rip off Britain the FelPro gasket sets were $110 each time (remember I did this twice!) I know in the US they're only 25-30 bux! It's also a good time not to have a Callaway!
All the best, Malc
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