Hello Hillfarms3 and
I am not sure If I can help you, but others here might. If you have a Ford chassis I believe the connecter is attached to the steering column behind the dash.
From your profile I see you have a gas coach, but more info would be helpful.
What chassis do you have? Ford, Workhorse etc.
If it's not on the steering column you might try using the search feature on the upper right side of the forum. Enter search terms like
ODB-II, (OBD- two capitol i's)
Ford, Alegro, location
Hopefully someone with more knowledge then I will chime in and lend a hand.