Need some help with choosing a shortboard?

I've been surfing a few months now i started on a 6ft fun board i already had good balance from skateboarding so it wasn't very hard to ride this fun board.I want to get a jp shortboard but don't really now if i should get a 6ft or larger.I'm 5ft 8in bout 119 lb.i was thinking of a 6ft 2in JP shortboard?any advise appreciated thanks