I see they state that it is a GC-1A, which was the first model produced in '46. It came with a Continental C85 which developed 85 horsepower. Later that year came the GC-1B which had the 125 horse C125.
The C85 in the GC-1A didn't make enough power for the aircraft to actually fly right off the runway. You had to keep in ground effect until enough speed built up to actually fly!
So sounds like they modeled this version rather well!
jack