Thanks guys!
We found the welch plug with the serial number. I'll be looking up parts this evening.
My buddy was there this morning and fired up the motor with one pull.
I'd suggested that he clean the motor, so he added some Dawn to the water tub!
Just kidding! He added the Dawn so that his little boy could play with the bubbles. He's a great dad with a great kid.
We noticed some exhaust coming from under the AV plate and are thinking that maybe that'll stop once he replaces the impeller and water pump with gaskets, etc. Does that make sense?
The exhaust we're seeing is in the red circle and can be seen in the video too.