RodStRace is right, I think. Before 1956, Texas used engine numbers in titles for most vehicles, then went to chassis numbers (1949 for Fords). Think California changed over about then, too. As long as you have the original motor in the truck, and the number on it matches the title, you shouldn't have any problems getting a new title. Maybe they'll let you use the chassis number (do a "title correction"), but you'll probably have to get a new, state assigned VIN, and a new VIN plate on the door frame. Doesn't sound like you're doing a resto, so that shouldn't bother you.
Here's a link to the TexasDOT website page for vehicle title publications:
http://www.txdot.gov/txdot_library/drivers_vehicles/publications/title.htm

The downloadable Motor Vehicle Title Manual should tell you what the forms and procedures are.