It it were I, I'd be concerned about this. I would want to remove any ArmorAll residue before going with 303. (And, yes, 303 and IZ products are what I use.) I would recommend you use a good and safe cleaner; me, I'd use either Meguiar's APC+ (properly diluted for vinyl) or 1Z PlastikReniger, because I have them on hand. If you don't have those, or don't want to order anything online, there are some vinyl cleaners available at WalMart, AutoZone, etc.; before my Autopia addiction formed, I used a Blue Magic (or was it Blue Coral?) Vinyl Cleaner that was pretty decent.