[bobcowan]

You don't need anything fancy. All you want is a solid base to mount the bell crank to. Any flex or movement will mess up your balance.

My manifold has a drilled and threaded base in the center for the bell crank. But it was too low for good activation though out the operating range.

I made my own base out of some 1" octagonal alum bar stock. Drill a hole in each end. Drill and tap each hole. Put a stud in one end, and screw that into the boss on the manifold. Bolt the bell crank into the other hole. Nothing fancy, but it works. I also used a steel thread insert into each tapped hole for extra strength. One of the big tricks, though, is that the cuts must be perfectly square.

If you don't have the mounting boss on your manifold, I don't imagine it would be that big of a deal to drill and tap a hole dead center in the valley.

I also made my linkage arms out of 3/8" alum hex bar stock. Same thing Inglese sells, but a whole lot cheaper.