The Holley Sniper Dual Quad system will mount up to a stock manifold (and Edelbrock dual quad intake) with no modifications.
The shaker base plate needs to be the AVS version to fit the 4150, the stock AFB version the carb holes are too small.
The AVS (Edelbrock/4150 version) will need modification the front area where the front fuel rail cross over tube is, more exactly the 90 degree fittings on the front carb stick too far forward and hit the under side of the base plate (first photo). I used a hammer and dolly to push the metal up to clear the Holley fittings.
Once the metal is pushed up a bit to clear the fittings the shaker system fits