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Just about any radio falls into that category, you really aren't going to make any vehicle side harness modifications. You'll wire the appropriate harness to the new radio harness and then plug it into the truck. The only exception is if you choose to do steering wheel controls some interfaces may require a simple splice into the vehicle side wiring, actually most will for the 03. Its something that can be undone in a couple of minutes and as long as done correctly will cause no issues down the road. Easy way out is skip the steering wheel controls and you're good.
You will lose the 2nd row radio controls and headphone outputs, no way around that. The functionality that a modern radio can introduce to the vehicle will far outweigh that for most people. Have you given any thought as to what exactly you are putting in?
