I don't understand the Anderson tank fill comment (maybe because I don't have one) but there's no reason you can't have 10 fill ports if you want. Bear in mind each needs to be vented - if you overfill, the water needs somewhere to go. Most of these fill ports have a built in vent tube and you probably don't want that in your cupboard. Behind it is just a big clear or white plastic tube that gravity-feeds to the tank. You'll need a tee and some hose clamps and some extra tubing. I've never had two ports but I've moved mine once and it was an easy DIY job...
