Welcome to the Z. I find it highly unlikely the brakes on the 3500 are the same as those on the 1500 but who knows. I'd call a parts dealer like NAPA or the dealer and get the part numbers for both. Don't forget to turn the rotors and lube (should come in the box with the pads) the back side of the pads where they contact the caliper.
If these are "spare" or "used" do NOT touch them. I don't play around when it comes to brakes, they are either do it right or don't do it at all.
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