Thoughts on converting a 90 gal high into drop off tank

[menac]

Hey Everyone

I am been eye balling the drop off tanks online and although I am eager to get one, I am not about to spend $600 or more on a drop off tank.
My friend is going to return a 90 gallon high back to me with a stand.
I figure why not convert it into a drop off.
I was thinking of adding a 1/2 glass platform 90 degree angle and creating the drop off that way. He drilled the tank but I have yet to see it since I get it back this Friday.

I am having doubts since I have never attempting this before. Do you guys have any suggestions or concern with doing this? Or has anyone converted a reg tank into a drop off?
Here a draft sketch of what I had in mind.
Thanks for the help

 

[alron]

Why not try to recreate a more natural aquascaping of rocks to make it look like a drop off. Fill up that elevated part with huge rocks forming a cave underneath then some thin slice of rocks on top. Then d slope in front and side more natural with other rocks where u can hang some sea fans or gorgonians