Extra (vacuum) hoses

[robinfla52]

I recently purchased a used '88 Bass Buggy with a Merc Classic Fifty 45 hp motor. Sat for 3 years. No spark. I checked kill switch etc. I gave up and purchased a used 1983 Mercury 50hp for $250. figured, what the hell. It ran and they just replaced plugs, fuel filter,had carbs rebuilt. I swapped them out but I notice two differences. There is a hollow vacuum type hose on the rear,to the left of the #2 spark plug on the 45hp and no connection on the 50hp. Also, there is a similar but seperate hose connection that goes to the lower portin of the motor behind the lower prop area, on the 45 but not the 50hp. what are they and do I need them on the 50hp Thanks.
PS: can I start the motor without hooking up to ignition just to test?

I think the one tube goes to the speedometer