I am having trouble installing the Magnum 108A. It is a little wider then a OS 91 and the stock motor mount will not work. [:'(] I am trying to use an adjustable GP mount I have but with it I cannot get the recommended 120mm distance from the firewall to the prop bolt. [:@] Has anyone else run into this problem? I think my engine is about the same size as a 120 two strock so I am hoping someone can help me with te issue.