In 1977/78 most Grecos were still Norlin ( pancake ) construction on the Les Paul copies. There doesn't seem to be fret nibs that I can see so a lower model. Those tuners also suggest lower model so probably a EG500 or EG450. U1000 pickups would pretty much confirm that as far as I know.
It has a rotary cut (1pc) veneer top which is a dead giveaway, pretty sure when you open the cavities you'll find a plywood top on a chambered body, it's an EG450