Me and my friend are in the middle of making our first fiberglass box and we are almost ready to fiberglass. I have a pretty good idea how to do it except for one thing. After you have applied the resin to the fleece/fabric and it is dry and u go to actually use the fiberglass mat do you have to fiberglass the inside of the box or can you do the out side of it. On all the tutorials Ive seen them doing the inside of it. I was wondering if this is neccesary.