I can tell you the 7R8T means a 158" wheelbase for a F-4/5/6 truck.

It should have a Canadian vin number on the left side frame rail in the engine compartment and under the cab just after the transmission crossmember on the same side. I assume its also missing the tag plate on the top center of the firewall in the engine compartment.

There should also be a plate beside the starter solenoid on the right hand on the firewall. Can't quite remember what is exactly on this one but might help narrow it down.