$28,000 and not willing to provide photos?
Told you that it had original power train and then "confessed" he lied?
DANGER! WARNING! DANGER! WARNING!
I would only hire an appraiser (restoration specialist/expert) that knows about 1954 Chevrolet trucks.
Where is the truck located in Florida? Maybe a member can also inspect it for you? Any chance it is near Boca Raton?
Good luck and be careful.