It's up to you. Inverted will look better, but will require that you either run a remote glow extension or put up with hassle of trying to get the glow igniter on/off from an awkward position. Carb tuning is a little more critical with inverted mounting, but no big deal, just take your time to get it right. Yes, you need to make sure your carb and tank centerline are close to the same height. You may have to cut some of the original formers or supports to achieve this.