Help with changing the location of my 6 gallon Suburban hot water heater

I'm  in my RV. I have already removed the support structure from the old location. And what I forgot to take note of is where is the plywood that supports the hot water heater is located in reference (vertically) to the water heater door frame. I attached a photo to help explain this question. The location (height) of the plywood support must be at the right location (vertically) so that the Heater matches up exactly to the frame door. Know what I mean? If you look at the blue line in the image, that's the edge (lip) of the door frame at the bottom of the frame. Does the plywood support shelf (pine board in the image) line up exactly to the bottom lip of the frame, as I have it in the pic?

Any help is much appreciated!!!