Welcome!
Nice score!
I wish I had one at your age!
I had to work and buy mine myself.
So.......................keep your Dad!
To verify your car, did you check the vin for the year and engine and such.
Also, check the data plate for codes.
Besides this site and others, you can check codes for your car.
Like engine size, color and year, just to check against what you really have.
The 100 mph speedo is correct for both '76 and '77.
In fact, the 160 speedo was last used in 1974.
If you have any questions, post the vin and data plate info, and someone will post a reply for you.
George