canopy for 125 & info.

[Ichthy]

I like the idea of a canopy and wish i had one for my 75gal so i've decided that for my 125, i'm going to have one.
I'm looking to have one built, most likely by my dad
But i have no idea how to go about it to show it to him.

I know i want a lid so i can easily change out the bulbs and between the tank & lights, have eggcrate/light defuser so my tank's temp. wont raise like my 75gal[which is 86]
I've looking around on here but i haven't seen any pictures showing a canopy with a lid.

Does someone have that- that i can look at? Or plans of one?

I plan on getting lights with a timer, any ideas on where to put it tank-wise? Is it better to have it by the lights or on a wall of the stand or is that just personally choice....

Also, where is a good place to have a 125gal tank..... Is it ok to put one by a patio door that doesn't have blinds/shades to block half of the sunlight?[cause i know the sun is really bright between noon to 3p, i dont want any fish to die cuase of too much heat] Would that be too much sun? Or pretty amount of sunlight?

I would like to know, is it possible to buy an overflow system at a different time? I know on petco.com you can build your own and select to have an overflow system, i like the one they used in their picture, but to save on money a little bit, i would like to buy that later. Maybe? Or is it better to buy it at the same time cuase of the cutting of the glass. I know it's better to have a Reef-ready tank but i believe for a 125gal, it's a bit more money.

I would like some advice/ideas on a canopy before buying the tank.
[tried to word it right to make sense, if it doesn't i'm sorry, i'm semi pickie when it comes to aquariums]