Generator electrical disconnect where to find?

[EKM]

I broke a stud off my generator side electrical disconnect. This is in the main panel and when on house power, this side is off. When on gen power, you slide the rail device over to expose the gen disconnect switch. Any idea on where to find this switch?
its off a 2000 420 AC.
Thanks for any direction....going to start with Flounder Pounder.

 

[EKM]

Actually a 50amp breaker. Blue sea 7287 is the part....funny thing was when I bought the boat it had one of these breakers on board in a box but it had the same failure point.