Shorten a tank

[Gary]

Might be something worth considering. I have seen people cutting odd curves or very think glass who first score the glass with a glass cutter, then they place a line of lighter fluid on the score line and light it, The quick burst of heat cracks the glass off.

I wonder if this would work on the tank, doing each side at a time.

In any case, I would recommend trying this on a scrap piece of glass first.