When I did the backdate, I did sand mine down, started with 150 and worked down to 320, IIRC. They came up nicely as there was some old adhesive or such on them. After that, you can apply a protectant. I use a Norwex product called Leather Shine, and then a topcoat of 303 to protect them from UV's.
As stated above, ArmorAll is crap, silicone based that attracts dirt and forces you into thinking you gotta keep reapplying it. Smart, right?