Working new projekt 2 batteries

hi im working on a Best Way to Mount 2 batteries on the bamboo for longer range, i already know how to Connect it and so but im looking for inspiration on how to vide it away under the Stock battery so it looks more integraded on the board Line the Stock one, im at the point of doin a "raiser" on the battery case to have room for the second one, im Thinking on cnc Milling a alu frame to raise the Stock case 15mm for the extra battery to fit. Any other suggestions? Hit me. I want it to be stylish and Fall in the "stock"ish look so no tape or velcro Mount I want it to be a long lasting solution

 

Two batteries will add weight and loss of ground clearance and space is needed round the battery pack or you could damage the battery pack as the board flexes. Why not do what I'm doing? Currently making the battery easily swappable by converting the existing case? Carry spare battery in back pack. Just a thought?