Converting 10-frame box into 8-frame box?

[reedyfork]

I'm not looking to disassemble and cut boxes, but looking to do something simple like adding foam and/or wood spacers on the outsides to turn a 10-frame box into an 8-frame box (brood boxes only). Anyone ever tried something like this?

Over the years I've noticed that the two outer frames in my medium brood boxes tend to be empty, only partially drawn, and seemingly just a waste. I figured eliminating those outer frames would allow them to be better-utilized elsewhere, reduce frames to inspect, and add a little insulating factor to the side walls. Any cons?

[Wally]

This is just a guess, but I would think the two outer frames would remain the same, for storage and insulation, and the brood nest would be reduced by two frames in the middle.