Those old Lawn Boy Pros were incredibly powerful for their weight.
Also, because they did not have an oil pump pickup from an oil pan crankcase, they were very tolerant of extreme attitudes.
Several years ago, I had a large corner lot which I maintained as a sort of showpiece. It was a nice lot with some stately trees on the busiest intersection in the county. Unfortunately it was bounded by cavernous county ditches.
I put ubolts on one Lawn Boy in order to attach ropes to pull and guide the mower along the sides and bottoms of the ditches.
To minimize gas spilling, I made an "all terrain" fuel tank from a modified 1 gallon Rotella T jug and hung it from the mower handlebar.
It worked great and those ditches looked like a manicured golf course green ... ( after a lot of work).