LiPo Battery Converter Touring Car --> Shorty to Fullsize

Bought a used Touring Car, but I dont have any full sized batteries, just my small Shortys.
Made a Conversion kit that should fit for all Shortys. Below the Shorty is a 2mm area where a brass plate could be mounted.

If you copy the size the brass plate will have ~60g with 2mm thickness. This should make the Shorty full-weighted :)