May be an obvious question, buuut..

[Dave]

Well worth doing, with this pin I've had to turn the fuel screw down nearly a full turn to clear the smoke at 26/7psi!

Your doing it all wrong then, your not supposed to turn anything down.............ever, too much smoke mean that you need more boost................not less fuel, that is backwards progress

Was going to contribute to this..... but in actual fact mark is 100% correct go find a bigger turbo