Panzerkampfwagen VIII Maus ("Mouse") 

Built this kit stock years ago.  After a discussion with some guys during my time on AOL the idea to do an improved production version was brought forward.  The changes to the kit are a copula for the commander, screens for the engine vents and changing the turret front slope to reduce the shot trap.  On my kit I did not do the top run of track.  I also shimmed the turret to clear the deck better and removed some of the front guard plates to clear the new turret front.  One thing I would recommend is doing up a length of track just before assembling the sprockets and using it to help align the sprockets.