I have a question about my NPO VSS-M because it's an HPA airsoft for now. I want to rebuild it back to an AEG. Wondering whether it can fit with a normal V3 gearbox, btw I don't mind about losing its special selector function because I have to install a ETU inside. I know the NPO one has different measurements with LCT. If you have the same airsoft as me, please leave your comment.