Al Pastor recipe using carrot juice and orange juice

There is a restaurant in San Bruno, CA, called La Paloma Mexican Restaurant, that has the most delicious Al Pastor I've ever had. I've tried Al Pastor at other restaurants and they've all fallen short, in my opinion. The last time I was there, I asked the waitress if she could tell me how they make it. Due to a language barrier, I wasn't able to learn much, but I learned this much: when I asked if pineapple juice is used, she said no but orange juice and carrot juice are both used. Has anyone ever run across a recipe like this? I would surely love to figure out how to make Al Pastor the way La Paloma does. Unfortunately, I live in another state, so I can't just pop in periodically to continually sample it in order to try to develop a copycat recipe. Help appreciated.