Stereo & Electronics - How to put 8" midbass in sail panel?

i am wanting to put an 8" midbass in my sail panels and was wondering how you go about gettin the hole to be a perfect circle for the exact cutout diameter and also what u used to get it that way....... i am plannin to use an infinite baffle subwoofer for this and high pass it at 80hz and low pass it at 300hz......... does this sound ok?

get an 8in template, trace it on, then use some type of cutting method ie. dremmel, air saw etc

I would recommend not mounting the midbass directly to the metal also, cut the hole then make a nice baffle out of 1/2" mdf to mount to. It will get tight in there though, good luck.