interchangability between years

I'm working on a '84 750. looking at parts on ebay they show many for '83 and many for '85/86. but but not a lot for 84. looking at things like an airbox or body plastic, do they interchange or is the 84 "different"?

 

Air box and bodywork will be the same 83 - 85. No such thing as a 86 VF750/700F. 85 VF700F got revised forks and brakes and some small electrical item changes (blade fuses for instance).

 

neither airbox nor bodywork from an '86 700 will work for you. i suggest you do a compression test on the engine b4 proceeding further or buying parts.