"Tim, you should have started
"Tim, you should have started a new discussion - your question may have got lost.
Anyhow, your Firestone is a 1953, twin cylinder made by Scott-Atwater.
As to value - not much. There are literally thousands of these small outboards out there in boat houses, garages, sheds etc.
If it's running it's worth maybe 50 bucks. If it was still in the original factory cardboard, had never even been fired up and was covered in the original packing grease it may be worth a few hundred.
It's only value lies if you have a use for it and can keep it going. A new 7.5 would run you close to a grand - otherwise, stick it in a yard sale and if you are offered 20 bucks - take it...."