I have a aspx page that looks something like this:
Some label
Some complex control
Keep in mind reording client-side leaves yourself open to issues in three ways.
Although it seems you want to do this client-side to save yourself some headaches now on the server-side programming, in the long run investing some time on this now to get it server-side will avoid these troubles.
If you're having issues getting the server-side code to work right with your custom controls post it and we'll help you out.