I use to work in the Shop.
sounds like the link got you sorted it is cool to recreate an old stick. The only thing with poly boards is the deck will compress especally with 4oz superlight glass, unless as you are reinforcing with glass but that adds to the weight.
If you can try a tufflight I would recomend it. They are very responsive to pop airs on and whip arround. I rode my poly surfboards when I started riding unstrapped it was unreal and i have't looked back.
Mergs
Rawson 6'2" is the go