I did this on my 350HO. The aluminum HO intake was functionally identical except about 1/2" of the port at the intake flange. They put a little more metal there and made the opening slightly taller, but it's not raised. I was able to fill that in with a very small amount of epoxy to eliminate the step. Since the ports are not precisely cast it was not even bigger than a standard port on some of them.

It was nice at first to have a functional choke with the crossover and yet it kept the intake cooler. That helped a lot with modern fuel, hot starts and response. Later on I replaced the carb with an 800cfm unit with an electric choke and put in simple block off plates.

Aside from minor performance and convenience improvements it looks cool. That actually counts for something in the hobby.

Some other notes of consideration, the 69-71 units are the best with the '72 units having a modified plenum floor that reduces volume and flow. It's a measurable difference and unfortunately the reproduction units are modeled after the '72 units. If you check around the internet there's an indepth article about it.
Also it's a decent amount of weight reduction if you use blockoff plates instead of the crossover. A stock cast iron intake is about 45 pounds, the Aluminum HO intake complete is about 22 pounds. If you use block off plates with it you get it down to about 13.

Here's the bonus round... because the intakes are essentially the same externally you can modify the cast iron unit to functionally act like an HO intake. Some eye protection and a cutoff wheel, a little grinding and you can remove the cast in exhaust cross over. Then buy a repro cross over for about $150 and drop the whole thing on. Or do the block off plates.
I did all this, divorced the water cross over and opened the carb flange. This reduced the cast iron intake to about 27 pounds.