please help me modify this shelf

My first wordworking project was an 8' tall plywood case with four shelves to hold canvases (Im a painter). I made the dadoes with a circular saw on a gravel driveway (!) I couldnt walk afterwords and I was hooked on woodworking after that. Now I have better tools: a table saw, router, etc.
Here's what I want to do: I want to get rid of one of the shelves (glued and nailed in) and also divide the shelves in half using some more dadoes and pieces of hardboard. I need to make the individual shelves narrower, they dont hold the canvases upright enough because they are too wide. Also, I need to get rid of a shelf to accomodate larger paintings.
Here are my questions:
1. What is the best way to get rid of that shelf thats glued and nailed in? Its 3/4" thick plywood and the dadoes are about 1/2". If the dadoes and shelves were a nice snug fit, I guess I would use a sawsall to cut the shelf out and then plane it down. However, since I did such a sloppy job with a cir saw, and not knowing what I was doing, the shelf and dadoes are very, very ugly and badly matched. So if I just cut it out, it wont look good and -- more importantly, may very weak at that spot. Should I cut it out and then add putty to fill the gaps or is there a way to unglue it and get the brads out? What should I do here?
2. To add in the new shelves, I can use a router, but I cant get it all the way to the back because there is a plywood back on it with about 100 brads in it. Is there a better way to divide the shelves?
Thank you very much for putting up with this long post. Any help would be appreciated. The cabinet is made from oak plywood so I wouldnt want to just start over...
Bob
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Can you post a digital; picture or three, on alt.binaries.pictures.woodworking ?
Get a close-up of the dados.
--
Jim in NC



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Will do, as soon as I get a chance.
Bob

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