Weber Carburetor Linkage

Linkage on the original FIA used a stand on the back of the left head to change the linkage direction from front-to-back to sideways.  Then, a longitudinal rod brings the motion to arms between the carburetors so that the final links act on the throttles the same way..

All the carbs are mounted in the same direction.

Original linkage
This setup has a mid-mounted external bellcrank to change the linkaged direction.  The standard ERA linkage attaches to the left side of the intake manifold.  The final linkage attaches to the top of the left throttle plate arm and the bottom of the right.

All the carbs are mounted with the fuel feeds on the outside.

4bbl Carb linkage here

Second design