Hey Steve!
Most like to use a popper rack.
If you don't have one, I've read that some will use a flat tray and cut the peppers in half, but leave them attached at the steam. This will make little boats and the cheese will not run out, because they are attached at the end.
Some folks preheat the bacon in the microwave and then wrap the peppers.
225* for 2.5 hrs should get you close on time.
Hope this helps a little.