Finless

I'm helping a friend/family with his car (not mine). Due to circumstance his car has been stood without being started for 8 years. I recently removed one spark plug (the easiest one / what a PITA that was / is there a special plug spanner?). I put my endoscope camera in and all looked fine. I turned the engine over by hand and all felt 'smooth' and the timing belt didn't have any cracks where it had been sat on the pulleys (I have recommended that he gets it changed asap). I also recommend that he/we change the fuel but I'm not sure of the best or easiest way to do that so would be v/grateful for any advice on this or anything else that needs to be done? The last time I seriously delved into an engine they still had distributor caps and plug leads (might even had horses at the front)! :) I would be grateful for any advice.