How heavy can those be?
Never heard of someone lightening their carbs via CNC cutting unless it was usage of existing lighter bowls, lighter aluminum main bodies, metering blocks and performing choke tower removals.

Toilets are different and perhaps meatier extra terrestrials.

Though very minimal being part of my ounce count drive last year, I've got T-6 aluminum carb mounting studs with aluminum nuts and lock washers on all four corners of the carb and a center air cleaner stud. That's about the extent that I have been able to go with.