how to make handles adornee in the center of multiple parts?

I'm making a custom building tool for my game but I need handles to be in between two parts like this http://prntscr.com/n0nb8y but instead it puts the handles on one part or the other. To make matters worse the adornee cant be to a model. There also appears to be no offset in the properties either. How can I get an effect like this or do I just need to make a invisible part in between them?

Effect I want: http://prntscr.com/n0nb8y Effect I'm getting: http://prntscr.com/n0neh0