While a reading of the letter of the law seems to indicate that you would be correct and would be able to pass on/differentiate charges ("The customer CAN'T 'elect' to use a credit card because we don't take anything else! Suck on that, legislature!"), my reading is that the "intent of the legislature"^ clause would almost certainly preclude you from charging credit card surcharges and that a customer who sued you for doing so would win.
^"It is the intent of the Legislature to promote the effective operation of the free market and protect consumers from deceptive price increases for goods and services by prohibiting credit card surcharges[...]"
^"It is the intent of the Legislature to promote the effective operation of the free market and protect consumers from deceptive price increases for goods and services by prohibiting credit card surcharges[...]"