Amazing find. Alcohol is well hidden in amazing combination that creates a bright, smooth drink.
To keep things sweet, I used a combination of regular limes and key limes for the juice - just juiced 5 regular limes, then over a dozen key limes to get an equal amount of juice. For the orange liqueur, I used about 3 shots of Grand Marnier, then filled up the rest of the cup with cheap BOLS triple sec. For the OJ, I used store-bought "not from concentrate" orange juice to save time. The almond syrup really added a unique twist taste, and should not be missed. Also, to save money and make sure it was not too strong, I followed the suggestions of others and replaced the 151 proof rum with a combo of the light and dark. Tasted amazing the first day, lost a bit of it's bright, fruity taste the next day; so I'd suggest you avoid storing it.