Everyone...

Thanks for the awesome feedback. I dug a bit deeper into the manifold sizing information, basically the height of the carb mounting pad at the front (A measurement below) and rear (B).

Here are the details:

PERFORMER RPM (1500-6500 rpm)
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Part# 7176
Manifold height DESIGN: A-4.9", B-5.8", Carb pad height = 5.35" ((A+B)/2), Port exit dimensions: 1.01" x 2.17"

VICTOR W-2 (3500-8000 rpm)
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Part# 2920
Manifold height DESIGN: A-4.15", B-5.70", Carb pad height = 4.93" ((A+B)/2), Port exit dimensions: 1.32" x 2.00"

Soo....as it turns out (and unless the reality of the casting is way off) the W2 Victor intake is actually a lower intake (at the carb mounting pad) than the Perfomer RPM piece. Point being, I am using the adapter plate with the RPM piece right now and since the "measure twice cut once" adage readily applies here I will run the Victor intake with the adapter plate first. If that fails miserably I will then pursue the re-shaping of the pad to accept the spreadbore carb.

My biggest worry here is that the additional volume of the adapter plate will just further add to the soft bottom end, but heck, it's only 3/4" thick and a stroker motor with a 112 LSA on the cam should help this out.