Transforming

Hey guys I´m trying to mod that Goku ( super saiyan god ) transforms in to super saiyan god super saiyan. I already modded that Goku´s ultimate attack is super saiyan instead of super spirit bomb and i also have the model for super saiyan god super saiyan but the only problem is that i don´t know how to make Goku changing his player model into super saiyan god super saiyan after using super saiyan pls help me