Putting a 70 280sl back together for my dad who couldn't finish it. It's been years since it was started so I'm doing all the usual filter changes, fuel tank clean out etc.. I removed the injectors to have them sonic cleaned but the person that assembled the engine years back did not put the copper washers under the injectors. I'd like to make sure I get the right ones if someone could direct me to a good place. Thx in advance. Rob