I was thinking of taking an MKE AT-94P (H&K SP89 clone) and registering it as an SBR in order to add a VFG and side folding stock. I was wanting the option of having the stock as well as just the flat end cap. How would one go about filling in the overall length of the weapon on the ATF Form 1? Would you have to list the overall length both with and without the stock or just one or the other? Thanks for the help!