To make a thinner chicken salad?

I do think the lemon would curdle the mayonnaise. In my effort to help you answer your question, it seems like a lot of people are looking to reproduce this recipe. Of all the copy cat Arby's recipes I have found, and those ex Arby employees, it seems that it is a mixture of good quality mayonnaise and sour cream, but the one you may be looking for was mixed with fat free yogurt. I guess I should try one of these!