Greg-
Don's advice is excellent. I wired my mic connector as he suggests and use a Ten Tec 701 (Electret element is built in), configured with an 8-pin plug. Excellent audio reports and the price is right: $28 for the mic!
Good luck and keep us posted!
73,
Cary, K4TM
K2-100 #5266
"I love my K2!"