JCell said:yes, or get an external wastegate welded to your manifold
B1GHAM said:the GT28RS has an internal wastegate with all you would need is the WGA (which is prone to fail, thats what you should replace)
ATP makes a good 6psi wastegate that is a direct replacement. It can be purchased directly from ken @ protegegarage.
LMK what kind of condition your current WGA is in, Id be interested in taking it off your hands for a good price (mine has a ripped diaphram and is leaking)