Good news.
I also run a factory induction system off the windshield on my 73 Ventura. Years ago I robbed the hood and Shaker parts from a 1974 GTO and it has been flawless.
The only issues I've had is when I tried to run a taller PM intake which required a shorter air cleaner element. It hated that deal, so I used a shorter Shaker instead. It never ran any better than the stock intake if as good, so I went back to the stock parts instead.
I was actually quite surprised that the factory intake (ported) runs as good as if not a tad better than the much larger rpm intake. You'd think the big 455 would like the bigger intake, but it kills off some low end power and doesn't 60' as good.
Last outing netter 1.59-1.61 60' times and 7.18 in the 1/8th mile at 95mph. The big rpm intake typically runs 1.63-1.64 60' and 7.20-7.30's in the 1/8th mile at 95-96mph. So you trade a little low end for stronger top and it still doesn't run any quicker.
Keep in mind that this is on the big 455 with CNC ported aluminum heads and 11 to 1 compression. I see all sorts of aftermarket aluminum intakes on much smaller engines making half the power. I'll bet the factory intakes even unported would be quicker on those engines as well........Cliff