I am in the process of reconstructing an old 10 speed Free Spirit bicycle. It comes with a Simplex rear and front derailleurs which I have read that not many people seem to hold in high regard. My neighbor kindly donated me a set of rear and front Suntour Superbe which are used but in magnificent condition. My question is: could I just swap the original Simplex for the Suntour? Tey look slightly different so I am anticipating having to use some sort of adapter(?) in order to use it. Am I in the right path? Or is it wishful thinking? I just would like to have a functional old beater without having to spent a fortune or even anything at all... Just one disclaimer... This is my first bike project ever. I would appreciate a kind soul who could give me some piece of advice on this matter. Thanks.