On my car, the airbox is to the left, and the intake manifold is on the right. Don't know how the V8 is set up.
However, you can just spray water at the intake manifold gasket. If the gasket is bad, you will get air bubbles.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".