Consulting Billing Practices

My company is having a difficult time agreeing on a billing practice for my (Consultant) time. I am Consultant and my main services are to design and prepare implementation plans for small/medium size networks, conduct business process analyses, recommend new technologies and recommend policy and procedural changes. Many days I am working on multiple projects for multiple clients. I would like to know how my collegues bill for similar situations. Our Account Executives would like to see my time billed in 6 minute increments, like a Lawyer.