Ignition switch

[cheesehead]

Does anyone know which of these ignition switches is compatible with a 1977 Westy? Or know the part number for a '77 ignition switch?
Both Napa parts
Part Number: ECH KS6658
Part Number: ATM 111905865L

Without taking out my switch how do I know how many pins my switch has? Has anyone here replaced their 77 Westy ignition switch?

[cheesehead]

I think I found it and looks like 111-905-865L so the second one should work:)
But if anyone has input in this let me know.