Making a window (replacing current one) question

[Blackhawk47]

so if i buy a sheet of acrylic like this.

and i unscrew my current window (has a crack n scratches all over it) what would be the best method of attaching the new window.

would it be better to just use double sided tape (a really strong one) round the edges or to try and make screw holes in the right places and screw it back on.

 

[Blackhawk47]

new problem. the screw holes need to be square. does anyone have any idea how to make these squares on the acrylic ( it uses this rivets kinda thing)

 

[Blackhawk47]

another problem ...is it okay to drill acrylic ... it wont crack or break it or something will it ? and what about cutting it to size? will a saw work or do i need something more professional