'Sport' is the label when it's not a Limited or Renegade. It's not an upgrade; it's the default. Options (like V6, auto trans, etc.) were available on the Sport.
I have seen plenty with no badge at all, no Sport, Limited or anything, just a Libby 4x4 with v6 auto. The limited/sport/renegade simply meant it had some base addons that changed what core features were on it. So, if you were at the dealer and ordering your Libby from the factory... and you started with a Limited trim level, you already had power locks/windows etc but if you started with a 'no badge' or base model, you had to add those things.
Think of it as just a starting trim level, not a factor in what you had when the order sheet was completed. You could order a base model and add every option/feature a Renegade had for instance... except you would not have the Renegade badge when it was delivered...
So, in the end, what does 'Trail Rated' add?
Not much

it depends again on what 'trim level' was the starting point...
I suspect in the OP's case we may find that a limited slip axel was the only defining point that 'earned' this badge...
I suggest that the badge means nothing, the trim level means nothing...
IMO take the VIN and generate the as built sheet, that tells you everything.
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