All fish tanks that are like 5g or more are tempered glass on the bottom, if they werent they would collapse from the weight of the substrate and water and everything else you put in them. I will garuntee you that your 92g is tempered.
Pre-drilled tanks are tanks that are drilled before they are tempered.. Then they temper the glass. Honestly considering how rare and expensive 92g tanks are.. I wouldnt drill into it.. I just wouldnt want to risk cracking the glass or having it shatter on me. Get yourself a good canister filter or two, and a protein skimmer..
I also recomend two heaters, My tank has a 300w and a 250w heater on each corner, to keep the temps in the tank even.
Also water flow in corner tanks is kinda hard to get working properly.. What I do is i put the spray bar on my 2217 eheim canister filter horizontal, meaning up and down, and i put it on the front corner of the tank, this way is pushes water along the front BOW of the tank and creates a whirlpool motion of water flow in my tank.. Then i have a Internal filter on the oposite side where the intake of the canister is at, and i have its spray bar pointed up for surface agitation and its pointed towards the back of the glass at an angle.. This creates more water flow and circular motion in the fish tank...
Lighting it kinda hard for these tanks, I have Power compact over my tank, and i made a custom top for mine since it didnt come with a top when i got it on craigslist.. I put the 65w power compacts on each side, left and right and have them facing front to back.. This way the sides middle and front of the tank are perfectly lit.. The only problem is the back corner of the tank is dark and so what i do is i have a smaller like 18 inch T8 light back there to light the back up.
Here isa video of my tank, the first one is when i first set up the tank, the 2nd is just one i made talking about how to care for discus and my disagreements with some people's opinions on them, but you can see the progression of the plant growth. Im trying to carpet the bottom with S. repens