I had a couple of friends who had these trucks back when they were new. Performance was pretty impressive but I don't think it would compare with what the one in your pics has to offer.
These are bringing pretty fair prices for a pickup and were faster than the corvette of the same year. of course performance was down on all American built cars in '79 but IIRC, the TLRT had the lowest ET of any American built production car of that year.