I'm assuming that the nuts will be metal. 7/16 x 24 is a machine size. Not all that common but used here and there. Do A and E use those nuts ? I'm pretty sure my 68 A does.
The way to make the nuts in metal may take a little more effort.
Usually the 3D printing is some type of plastic. I could print out the nuts in plastic, then my son's friend suggests to make a mold off of that if it is to be made like the original.
There may be two ways to try the threads.
One is to just have them printed out in the mode., but I don't know how accurate the thread generator in the program is compared to real world.
Second option is to mold/print them as "blanks" and run a tap or die down them to put the thread in. this way will make sure that any "estimates" in the model for the thread are not a problem...
3D printing is good to prove out the geometry of your model, but may not be a strong enough to live in the "real environment"...