Can anyone silicon really well?

[headdr]

I just broke the front glass of my new 100 gallon Cadlight project tank. I bought it for $200 dollars. Had a few hairline scratches and 2 good ones on the front. In hindsight nothing that I couldn't live with. I tried to grind and polish out the scratches. Actually got the deep ones out, just couldn't get it to polish back clear. Turned it on its side and the heat from polishing did me in. I know a guy who can get me some glass so I am thinking about replacing the front. Anyone ever tried this?