Old McCulloch

Any one here know anything about these older motors, I have a 9.9 ( I think ), the shroud is broken and does not say what HP it is.
It came with a small 14' aluminium that was given to me the other day, it has electric start and I hooked my TM bat. up to it and it turns over but as for any information, I have not found much on the internet.
Like mixture ratio, age, how to tell what HP it may be.
The shift selector works but I have only tried it by hand turning the prop, tommarrow I will pull the spark plugs and see what they look like, may be go as far as hanging it off the back of the boat in a 5 gallon bucket, Hummm but I do not have a fuel line hookup that looks like the one on the engine, I guess I can bypass the coupler and run a gravity feed something.
Any information will help, and have a good day!
Rusty