If they haven't been maintained they can be stuck in the motor pretty hard.
Mercruiser or Volvo/Cobra/OMC?
It doesn't take 5 minutes. The fastest I could do one with a brand new setup, never installed with parts laying out is about 5 minutes....
You will need to double check the engine alignment while it's out.
It's something I could help you with and sure wouldn't charge $140. Might even just takes parts for trade.