REGRET

I regretted selling my first Mopar before I even handed the keys to the new owner. It was a double-black 1973 340/4-speed Challenger (non-Rallye, no vinyl) that was, at the time, too far gone to save. In 1989, AMD, Goodmark and the others didn't exist and typical of E-bodies it needed every structural member rear of the back seat. I was able to keep track of the car for about ten years, but then lost the trail. It took me 25 years to find a suitable replacement, which is a '74. The '74 is getting a 340 and 4-speed along with everything else my '73 had, plus upgrades I wanted when I was 18 but couldn't afford (Six Pack, T/A hood, etc.). I still have the original Pistol Grip from my '73 as well as some minor parts that I'll use. I'd still rather have the original back, but by now I assume it's soup cans. If I found it, though, I'd restore it right back to build-sheet specs (I have that, along with all the original dealer paperwork and MSO).
It's your car, so do whatever you want with it. Make it what you want; there's no shame in that. If you want to spec it just like your old one, have at it. In my case, I've no doubt a double-black 340 Six Pack 4-speed Challenger has better resale value than a stone-stock Dark Moonstone, white vinyl top 318 automatic would've anyhow.
Mostly, have fun with what you've got. You might find yourself just as much, or even more in love with this one down the road.
Wishing you the best with your health issues. Hang in there and stay positive. Attitude does make a difference!