As I read your last post it seems that there are a few initiatives going on here.
1. Increase sales.
This looks like you need to take more market share from your competition. I am not in sales or marketing so I cannot lend to much assistance here.

2. Integration of Parts and Service
We have an integrated Service and Parts system in place now. Let me just start by saying that it doesn't happen overnight. Moving Key people away from what they are good at is not a solution. However cross training them with the service department can help a great deal. Having a clear understanding of what the other staff deals with every day can change your interdepartmental communications. Also it can bring about changes in processes and procedures that are more efficient. We use a team approach for almost everything and are roughly structured as follows.

Service Coordinator -Not a Dispatcher! Techs for the most part control their own schedule, however the SC can get team leaders involved to get calls done.
Parts advisors
Tech Team Leaders
Tech Teams (Think North and South or County 1 and County 2)
Billing Team

Any one from any team is empowered to hold accountable any one from another team within the normal business processes. Other issues are handled by Team Leaders or Managers. The key is that there is are very clear processes and goals defined.
One last note. We heavily use technology as an "enabler". It is tool, not the solution. We have made those mistakes.