Do I need to get the glass cut on this tank ??

Hi,

I've been given a 48" x 15" x 12" glass tank, and I'm wondering about
its construction. It has been in constant use for over ten years I
believe. However, I have read on various websites that tanks should
be constructed with all four walls sitting ON TOP of the base and the
end walls fitting inside the front and back. On my tank, the front
and back are butting up to the edges of the base, not sitting on top.
e.g. (looking at the tank side-on) :-

B F
| A | | R |
| C | | O |
| K |___________________________| N |
| | BASE | T |
|___|___________________________|___|


The sides are fitted correctly, on top of the base and inside the
front & back. The glass is 6mm front, back & base, 4mm sides.

What I would like to know is whether this is a problem ? Is it a
*dangerous* way to build a tank, or is it just OK, but not the
'preferred' way to build it ?

Because, if it is inherently unsafe, then I will have to get the end
panels trimmed in width and move the front & back onto the base.

I am not happy about the integrity of the sealing, so I will be
dismantling the whole tank anyway and rebuilding it. At one point,
there is a 2mm gap between one end panel and the base, and only the
silicone bead on the inside of the tank was stopping a major leak -
there is nothing at all between the glass surfaces, bar 2mm of air !

Whilst I'm here - what can I use to completely remove the old siicone,
once I've cut off the bulk of it ??


....or am I just wasing time & money and would be better off buying a
new, professionally built tank ?

Many thanks in advance,

Cheers,

Kev.