Show off your truck's organization to your potential customers in your marketing materials, like your website.
If you spend time organizing and cleaning your truck, this is a signal to customers that you'll also be organized and clean on the job.
Think about who you'd trust to work inside your home:
Is it the guy with the stacks of receipts and invoices on the dashboard and a dimly lit cargo area with the tools thrown in a pile?
Or is it the guy with the strips of LED lights, labeled bins and boxes, and iPad with a Square card reader?
Be the trustworthy guy.