single line drawing that, I assume, you've been drawing for every addition and modification. That dark and stormy night 2 years down the road is going to be a lot darker and the extra fuses aren't going to do you any good if you've been off watch and asleep 20 minutes when the crew guy comes down and wakes you up. Especially if it's the third night into this dark and stormy when you start to trouble shoot why the radio won't work. I'm just saying that a well done single line drawing has saved me a lot of headache time over the years. I have drawings for EVERYTHING and it was time well spent. I drew them long hand, a technique I learned in "Mechanical Drawing class" in junior high school about 55 years ago. I understand that you can draw them now using computer programs now. That would be a fun project which would have a huge pay out at the end. I highly suggest it.