Removing Intake Manifold

[S. Crosbie]

    I am about to remove the intake manifold to: 1.  replace O rings on 
the coolant distribution pipe under the manifold, it is beginning to 
leak in that area  2. finally put in    my group purchase distributor 
gear and replace dist. rotor.   It looks like I need about an 8" long 
6mm allen wrench.  The one I have is too short, and the socket set I own 
is a 3/8" drive and it looks like only a 1/4" drive will fit through the 
hole in the manifold.  Has anyone found a good source for a tool to get 
at these bolts?  I have looked at a couple of local auto parts, and tool 
shops and haven't found anything that will work.
Thanks for your help,
Steve