Please, help me tune my setup
 

right now i have a 62-68-13 over an s475 in my 98 12v, i have a 35mm external wastegate, along with the internal gate on the s300... i can still make well over 50psi at no where near full throttle, my pressures will run about 25-30psi on the s400, at about 50psi overall, will a bigger external gate help me at all to keep overall psi down? i have a head at j&h performance right now getting rebuilt and cut for o-rings, and giong to replace the exhaust manifold so wondering if the bigger gate will help or not, i also want to put the 140hp sticks in, but want to keep everything under 65psi if possible, thoughts???