I'm trying to loosen my distributor clamp bolt (10 mm longwise). My vacuum pod appears to be in the way of an approach with an open end wrench, as does an injector hose - do I need a special tool or socket adapter? Surely it cant be meant to be worked with an open end?

1/8 turn at a time with an open or boxed end wrench.

I was successful one time getting a 1/4 swivel socket on it.

Pain in the ass.

I bought this at the local PepBoys

http://www.pepboys.com/product/details/559...tools/wrenches/

It works flawlessly

I have never had a problem accessing the clamp bolt. If the vacuum can is blocking the bolt, it is timed wrong or the drive gear is installed wrong.

I got it - it was a little stiff but it freed up. I timed it to about 5 degrees in front of the 27 deg advanced timing mark and it runs great - I think it was a little retarded - assume it's like most bug/square back motors (I have 1.8) and it runs best at 32 degrees total advance. It cleared up the backfiring on deceleration and it has good power thru all RPM ranges with stock fuel injection.

If your stock injection is L-jet, your timing is wrong. It should be at 7btdc. That is why the vacuum can is covering the clamp bolt.