iPad Mini Lightning Cable Dock

I need a way to keep the iPad mini lightening cable plugged in (at the iPad side) to an external GPS. We use a thick heavy duty 10ft Cable which is thicker than the Apple made lightning cable. The Ram Mount won’t work we’ve tried. I thought I’ve seen a bungee type case that kept the lightening cable held in but I can’t seem to find it on the web. I know someone out there can help me.