Trying first idea
Thanks for the quick reply!! I was working along the lines of your initial idea which seems the cleanest to me. it also allows me to reuse some other functions I have going on when the form is submitted.
I copied the form from the working Add To Cart button and have it show if that item is in the cart. I adjusted the form processing code with this line: $ATC_AddIfIn = 4; (from 0) which is supposed to allow the values to be replaced. I have the hidden Quantity field set to "0" but it still does not remove it from the cart. Are there other lines of code to consider to get it to work?