This is a longer version of http://www.thingiverse.com/thing:27865 in both directions giving you more support and filling the HBP with a full 5" across and high.

Print one set out for the front panel of thingiverse.com/thing:23386 slide them on and slide your front panel on and off all day long.

If you don't have laser cut parts you can cut square pieces of acrylic and it will work just as well.

For the front get a pieces of 3mm acrylic cut to 15-3/8" Wide by 8-3/4 Tall.

They would also go well with these nice little finger handles. thingiverse.com/thing:27532 by thingiverse.com/Fastrack

These longer versions are to long for the side panels so use the orginal design for that.