The sticker on my newly purchased, used Coleman Powermate Vertex 7500 Watt Generator is faded so I cannot make out the model number so as to order an owner's manual so I can set to repairing the generator. However, it is a vertical model using a 14.5 hp Briggs and Stratton engine, model 28N777. Is there any way I can find out the model number and through it the parts numbers I may need to replace or repair?