Upgrading Document Reports to RTC: Best Practice?

I’m currently doing my first upgrade project from Navision 3.70 to 2009 SP1. Where most of the steps are very straight forward (when you have experience with NAV upgrades) then upgrading the order/invoice reports are causing a bit of headaches.

With a new version which functional/programming wise is changed much more than a bit, then I’m always starting with the new version of the report, eg. I’m using the standard report 205 to create the custom Order Confirmation report.

Then I’m Transferring the layout (Copy Paste) from the old customized report to the new in the classic client. In Visual Studio I’m trying to recreate the new layout, mostly by removing most of the existing fields, as the client is using paper pre-printed with name, address and logos.

But I guess that anyone who have tried this quickly figures out that this is NOT a good way to do it.

The reason is the rather confusing SetData and GetData, where a lot of “lists” has been defined to show the data in the page header using Code.GetData(x,y). Whenever I have removed a field in the classic client, then I need to update this definition, and also the list references.

But what is really the best practice for upgrading document reports to RTC?

Is it to upgrade the report in the classic client and the have the system suggest a new RTC layout?

Or is it the way I have described above?

Or is it an entire different way?