My lennox 80MGF control board, 1173-1 0715 100980-01 EGC1, has short circuited. I read zero ohm between the power input terminals. It is tripping the 15 amp circuit breakers. As I am looking for a replacement I have several questions hopefully some one can help.

(1) Could the board be damaged due to an external part, such as a bad blower motor? It would not do any good if I replaced the board if it could be damaged by another failed part.
(2) I see several boards advertised for this unit with major price differences, are some of them equivalent? how do I read the model number (which part is important)? Could I use 1173-1 0639 100983-01 EGC1 or 1173-1 0612 100990-01 EGC1?

Thanks.