How do I make my own version of High Noon?

I fucking love High Noons, I can kill a whole 12 pack on my own and maintain a great buzz while the water in it keeps me from dehydrating too much.

Problem is that it’s economically garbage, there’s no reason to spend this much when I can buy some Chopin, a bag of limes and topo Chico and do it myself.

Problem is that every time I tried making it the seltzer loses its fizziness and tastes super flat and gross.

What I love most about high noon is how the flavor lasts but isn’t overbearing, how it also maintains its bubbly fizz while having vodka in it.

I was wondering what the proper ratio is here and how I can go about doing it, potentially even scaling the oz of vodka without compromising the actual flavor and fizziness.