I do appreciate all the feedback I received on this thread. I wanted to update you all on what I ended up doing. So far I have decided to not mod the car further, still deciding on potentially rolling back the few mods that the previous owner did. I successfully have it tuned for 87 octane gas now, which will save me about $11 in gas a week! I do recognize the adage of "If it ain't broke, don't fix it!" but in my case, I was reasonably certain I could run my Bama tune safely.
I have three paths ahead of me for this car:
1. Mod the heck out of it over the next couple of years: Cams, exhaust, all ford racing parts such as the intake manifold and throttle body, body kit, new paint job, custom dyno tune, etc. Then drive it till the engine dies.. buy a rebuilt/reforged 4.6L and drop it in and re-apply my mods. So on and so forth. This is the most fun option but it does not make sense financially as the car is only worth at best re-sell value of $10k, I am paying/paid $12k which was KBB at the time.
2. Keep it exactly like it is, finish paying it off over the next 1.5 years. Re-sell privately and use that cash + savings to buy a new mustang.
3. Revert the mustang completely back to stock under the hood (including the stock tune saved on my Bama tuner), get some catalytic converters for the exhaust. Pay it off in 1.5 years. Drive it till it dies (4-7 years estimated time) and move on to another mustang.
I would like your feedback on what you would do if it was your mustang in my situation. I make a decent living and can easily afford my car payment, but my goal is to pay it off sooner rather than later. If I am modding or saving for mods then it will delay that plan. The mustang does need some paint/bodywork but nothing major.
I love the platform of the S197 as I feel it is the closest to the original mustangs I will ever get with my current financials lol. But I also am enamored with the tech & suspension packages of the new mustangs, as well as the looks and paint colors in some cases. I would consider an EcoBoost simply for the fact it makes an excellent daily driver. But enough talking about the newer mustangs I can't afford atm anyway. Thank you in advance for your thoughtful and constructive feedback!
PS: I attached a current photo of my mustang

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