Brief Questions re used 1998 TM

I am aware that between 1995 and 1998, TM moved away from wood lower boxes to aluminum boxes. Although I have a call into TM, would anyone know off-hand whether the 1998 2720s were aluminum or wood? Also, does the raising and lowering of the top half cause circle marks, or any marks, on the lower half? If so, why? Thank you, in advance, for your input.