um get rid of any colourfull bits cos if u want that to be player colours your best to leave it white or grey. and dirty that*bitch up!!!! just get some metal texture right and make a new layer in photoshop then make that transparant to a nice level. and erase the bits u dont want the effect to be on and bam you got a dirtier texture for her.
oh and i know the overlord is long but the apoc is more square shaped, mines looks fine in game. note thats an old texture here.
oh and its about the same size as an overlord mabye slighty bigger but it looks much bigger cos its not as long