I found a very minor ding in the seattube of a Nishiki I just picked up. It's hard to notice, but annoys me nonetheless. This is a very short frame but I do not believe the current seatpost reaches the ding. I'm assuming that I can just get a longer seatpost in the correct size and essentially pushout the ding in the seattube with the end of the seatpost as I push it in. Is this correct or will this not work, or worse, will I screw something up? Thanks!