Short and overweight – tuck in or untuck shirts?

I am 5’6 and 245. My profile is what kills me – my stomach is low and sticks out quite a bit. Being short makes it so much worse.
I have a hard time finding shirts that fit well but are also the right length. Most shirts I buy end up too long and I look horrible.
I mainly like to wear polos, but the size that fits right otherwise (not tight, doesn’t hug my stomach, sleeve seam doesn’t start too low down my arm) are all too long, I feel.
In a video of yours I watched on youtube (rules on tucking in a shirt), you stated to follow a 2-in or 4-in rule. My shirts always seem to be 4-in or longer down, and being short I have realized that is a bad thing.
So – considering how my stomach protrudes, should I even consider tucking in my shirts? I have button downs that are casual and not dress shirts…sometimes I try tucking them in and checking myself out – I look ridiculous because of my stomach. I DO try sucking my gut in, but that’s just uncomfortable. But I also heard in the video to “own your look”…
So what is your advice for a short man who’s stomach sticks out?