I've been helping to clean out my uncle's apartment when he's been placed in an assisted care facility. I found this open-faced pocket watch and it still works, although it looks very dirty. I don't know how to set the time. I tried pulling out the stem and turning it, but that just winds it. I asked my uncle if he wanted me to inquire about getting it cleaned. I wanted to know about how much that would cost, if it would be worth it and to whom should I take it? Also, how do I set the time?