Well... I don’t like this idea, but there is another alternative in which you would be able to use the same stand.
Basically, get a slab of wood (I’d use something stronger than plywood) that is flat and large enough to cover the whole tank bottom. And sandwich this between the stand and the tank (assuming the stand has a flat surface). This way, the whole tank would be supported by a rigid structure, the wood plank. The risk that you are trying to avoid is that you don’t want this wood to flex at all over those final 2” overhang. That could cause uneven stress on the tank and cause catastrophic failure.