Hewett

Hi All, I have been given a Bultaco, I thinks its 350cc not sure what model it is, frame no. JB 19100625 ENGINE NO JM 19100625 it is complete but a total mess , my intention to restore nut n bolt, have had a few Classic and Vintage cars so a bike should be in my capabilities! but really need to fully identify the model I have, can somebody help? I have photos which I can upload if that helps! thank you all in advance. Guy