I have a 1973 750 commando combat with out a spin on oil filter. I was told that Norton started installing these on late 72 models and was wondering if someone could verify this info.The engine and frame numbers match which is 209XXX. Is it possible I have a early 72 engine or is this guy all wet? I bought the bike in 1999 and it,s been in storage ever since. I plan to restore it so I will probably be on here quite a bit asking for help.Also would someone be able to steer me toward a good parts supplier?