I was going to tell you to ask Bill B about this but I looked at the link you gave and it WAS Bill B's recipe.
Anyway, do the math and break it down. Basically you just need to determine how much Pectic Enzyme and Yeast nutrient. Different brands are different doses and many are listed in one gallon increments so just break it down. Still use a whole packet of yeast. For the Sulfites I would just use one Camden tablet per gallon. Take an SG and adjust as needed. If you have an acid test kit test that and adjust as well. This wine can come out a bit tart so if you adjust it prior, it will be smoother but I have to say, Bill's version was very balanced with the sweet and tart.
BYW, I am one of the lucky ones that got to sample this wine and even bring home a bottle of it from that particular Winestock. I have made it a couple times and love it. I am even seriously considering planting Pomegranates to make it fresh.