15 gallon tank being used as the sump, 24x12,12. The side panels of the tank are 11 7/8 inches, and that is 'glass-on-glass' fit. When I get my glass baffles cut (hopefully tonight), should I go with 11 7/8 inches wide, or back it off a 16th of an inch and get them cut at 11 13/16 inches? I'm concerned that if I get them cut as an exact match (11 7/8) then when I try and put them in I won't be able to. With the lip of the tank, I can't just slide the glass down, I need to angle it it sideways to get it in the body of the tank, and then slide it into position, but it it's an exact match, will I be able to do that without breaking it?