Tub Leaking

Had this dishwasher gave to me by neighbors who were moving out and just completed my first dishwasher installation. It had set for about 4 months that I know of. Any way turned the water on and checked for leaks and found none however, when I turned the dishwasher on and let it fill, water was leaking all around the motor. I removed electrical power immediately and shop-vacced the water out of tub. I am assuming this is the main tub seal that is leaking. How hard are they to change and what other possibilities are there for the leak around the motor? Not real sure on the age of this just took a wild guess.

Thanks for your time and help on this matter!

OleBones are tired and aching