All this is good, but as currently framed, the owner will only grudgingly upgrade, at best.
Maybe try changing the frame. Get the owner/CEO/COO focused on operational reporting (non-period, non-financial) that he isn't now getting. Show some sample, canned dashboards (Sage Intell or BizNet) as bait. If he wants to start exploring how he can get daily/weekly data like that, then you focus the the Vision to that. Propose a small project to just identify what they can do to achieve this, and the upgrade, and more, comes out of that.
Your investment in that is maybe 20 minutes to pull together the visuals, and 30 minutes on the phone with him if he bites. In the phone call, you aim for a verbal agreement to the Vision project, complete with the price to do it.
80% chance you don't hear anything after the email with the dashboard lures. But it's 95% chance you will waste a lot of time if just talk upgrade and compatibility.