Taking a reefer unit out permantely. Plugging the hole left behind.

Hey everyone. I am new to all of this. Getting ready to buy a medium duty International 4700 box truck with a reefer box on it. I am wanting to take out the reefer unit and plug/seal off the hole. I assume there are panels or something that can be bought for this issue. I am needing the reefer box for the insulation value but will heating it during the winter instead of cooling. I run a mobile truck wash business and need to be able to keep the box heated during winter if anyone was wondering why I am doing this. What piece called that I need to put over the hole that the unit will leave behind and where can I look to find one. Sorry for the newbie question but any help would be appreciated. Thanks.

 

I just figured maybe some one made something for this application. I see alot of box truck with those aero looking (cones?) on the front of the boxes and thought that they were covering up the reefer hole.

 

Lets see if I can load this photo.

 

Something like this or flat would be better. I want something that has a plastic or aluminum covering on the outside.