Congratulations, my name is Jennifer as well and I picked up a C code 18.5 WSM from Craigslist a couple week ago for $30.
Here is my thread about it: http://tvwbb.com/showthread.php?49661-Picked-up-an-18-5-quot-WSM-off-Craigslist-today-for-30
My top vent has a C code on it and the damper...