Two, unless it gets augmented aftermarket with a lift axle.
one
2
The F750 was not in production in 1990.
The Ford Fusion has 2 axles.
The F750 was not in production in 1965.
The F750 was not in production in 1993.
Many websites will have Ford F750 parts. Autozone is a popular and reliable website to look for these. One other which is an option is called Partstrain.
The Ford F750 has a higher Gross Vehicle Weight Rating, and more powerful engine options available.
69
According to the Ford Website, the GVWR for the Ford F750 is either 30,000 or 33,000 lbs depending on how the truck was configured. http://www.commtruck.ford.com/ctw/default.asp
one
Depends entirely on which transmission you have with it.