pretty large brake fluid leak as I just topped my reservoir off a couple of short drives ago. I’m pretty new at this so I’m not sure where it’s coming from. my hunch is either the rear wheel area or this line that’s going above my rear differential. however i can’t tell if it’s my rear differential itself that’s leaking gear oil or if it’s the brake line above it
the oil has a sulfury smell when I get up close to it but it isn’t super super strong. here’s some pics if anyone can point me in the right direction of where it looks like the leak is coming from

When I do my own work (services, parts swaps, invoices), I end up with phone photos + random PDFs and then forget what was done when.

How do you keep DIY repair history so it’s useful later — paper folder, spreadsheet, notes app, something else?

I’ve been building a small digital service-history tool for myself (log jobs, attach invoices, keep mileage with the car). Curious if other DIYers bother with that, or if paper is enough until you sell.

Not trying to push anything — just want to know what actually works.