carburator spacer for 390 on 66 tbird

[kapejo]

I am installing a autolite 4100 carburetor on my 66 Bird. The carb spacer is wedged shaped...appx 1/2" down to an 1/8". Does the thin side face the front of the car or vice versa.
- Thanks

[Yadkin]

Notice how the engine is tipped back. The intake manifold and spacer are set up to make the carburetor more-or-less level.