Excellent build.
I learnt to wash seat belts from a expert so to say.
To clean seat belts, pull them all the way out and put a soft clamp to keep it extended. Take it out the car and carefully close door on it. The used parts will mostly be outside. Soak the seatbelt with clean green and allow to soak 30min. Then take a bucket with hot water and rinse massage belt. Reapply clean green and repeat till bets are clean.
Now if u think leather gets dirty , u gonna be in for a shocker when you see the crud that comes out of a seatbelt.