The rocker cover will be replaced by a RS1600i one as soon as I get it finished.

Main reason for the external wastegate in my case was that it makes easier to locate the turbo as you no longer have to worry about actuator aligning etc. Power wise I don't think it makes a lot of difference compared to an integral one. In my case after changing the inlet and exhaust manifold the engine made about 10% more power with the same boost level. Also the boost curve is more stable, no spikes and holds 23 psi all the way to red line