I will be entering my first competition tomorrow. Can you think of any last minute adjustments I should make?

Last night I did the big 3 in 2 guage wire.

Ive got my subs facing fowards and the box is so big it pretty much blocks off the entire trunk. There is prolly 4 inches on each side of the box and 4 inches above the box that leads into the trunk. I was going to fill in those gaps today with MDF board but I can't find anyone who has the right color carpet.

Would feeling those gaps in make a pretty big difference? If so is there something else I could temporarily feel them in with?

Also I have seen this question asked before but never answered. Most people know your system sounds louder when you dont set it with a dmm bc it is clipping. But I am wondering does the mic think it is louder?

Any suggestions or anything for me? Thanks.