One problem with "jacking" the front of the tank up is that the tank is no longer supported on its sides by the two rubber pads that are attached to the frame. The tank is only supported at the front and back and has the ability to rock from side to side if you push down on the tank. With only a 1/4 inch clearance between the tank and the stacks it could dent your tank. I have a 97 Standard with an IS tank and V-Stacks and my tank did get marred. When I recently repainted all my tins I wasn't about to let my new paint get marred again so following is what I did. (Besides, it just isn't good sense to only support it in 2 places when it was inteneded to be supported in four, it puts extra stress on the tank mounting ears.)
I used a 1/2 inch spacer in the front. I then experimented with different thicknesses and determined a 1/4 thick spacer strip on each side to contact the frame rubbers was just right. I super glued them to the bottom of the tank in the location shown on the picture. The tank no longers rocks.

