After changing all 5 glow plugs on a 1985 300d turbo and inspecting fuel return lines from injectors i failed to put #3 on correctly. During a ten mile drive after
doing this work that #3 return line came off losing about a gallon and a half of fuel under the hood. My question is should I go beyond cleaning up with rags and elbow grease and use a gunk engine cleaner and water with regular hose pressure or pressure washer. I always wondered wether the gasket around fuse box on fire wall seals very well so would using water do more harm than good?

 

Wipe it down with rags, get the puddled fuel taken up, that will remove any fire danger, beyond that it just depends on how clean you want it. If you use water and soap, stay away from glow plugs, and electrical connections as much as possible.