I am creating this post simply to have an easily searched post with a link to a how-to to accomplish this. The question has been asked here before but a clear answer has never been posted. Thanks to @murgero for posting this link in another topic.
Of course all of the steps in that linked article are not necessary - I have not gone through it step by step to determine the exact steps required.
And most importantly, keep in mind that this is an unsupported modification meaning that when you upgrade your Mail-in-a-Box to a newer version, these steps must be repeated as the changes will be overwritten.