I used to be more organized.
I kept service records, receipts and notes on almost everything.
Now? Not so much.
I do keep downloaded tech articles. Magazine reprints. catalogs to retain part numbers and various tech tips.
A buddy of mine that is otherwise a convoluted mess, has a binder with almost every modification he has done well drawn and detailed to his Challenger.
I do have notebooks with handwritten text. I've written about every nut, bolt or screw that I have touched. Engine builds, tuning, brakes, suspension... everything. This helps keep me from trying stuff that didn't work before. It also serves as a blueprint as to what actually has worked in the past.
What about you guys/gals ?