Why not just make a brick that creates a turret of a certain class? It could be like the car spawn, only more "turretish", and when you wrench it you can select from a list of different turrets. Then you could have the Blockguy sitting down in a seat and when you turn the turret it pivots on the base or sometihng. Sorta like the AA turrets in BF2 or the EMP turrets in BF 2142.