d15nonvtec824

If you get a BANKS iDash you can see actual DEF level as one of the options to display among many other things

From everything I can find, this is the one for you, its Alpine Umber leather for Denali Ultimate 87842524 - Armrest Assembly 2023-2024 GMC Sierra 1500 | GM Wholesale Direct

If you have ARC in the SLT trim, then yes. If the ARC option is not on it, then it would just be the shift point change.

Yes, for most trims (with ARC optioned) it only firms up the suspension and changes the shift points. For those that have the 6.2 motor there is an "active exhaust" which brings the db's up a bit.

If you already have refresh model, then why trade in? are you after a certain motor?

Yes, for sure you will feel it all and will be much more sensitive through the steering wheel

i am not a chrome fan either, but sometimes it works! now i just have to swap the grille badge.

so you just wired the tweeters into the factory dash wiring?