The 20mm cannon on an F-16 is the entire assembly labeled as items 63, 72, 73 and the ammunition is 78.
How do you envisage this as other than a fixed installation?
It's the square-cube law in action (twice over). Going from a 12.7mm to a 20-25mm bullet... twice the diameter, four times the crosssection, eight times the mass.
The 20mm cannon on an F-16 is the entire assembly labeled as items 63, 72, 73 and the ammunition is 78.
How do you envisage this as other than a fixed installation?