I'm applying to schools through both TMDSAS and AMCAS and am planning to use Interfolio to request my LoE/LoR. Interfolio has a setting to input your ID # for both services so that it is placed in the correct file, but TMDSAS's website states that it must be within the actual letter. So now I'm wondering if I have to bother my letter writer's to make an extra copy with the TMDSAS ID on one of them, ask for just one copy that has the TMDSAS ID and send that to the AMCAS schools too, or assume Interfolio's system will find the right file (worst option). Has anyone applied to both and can share what they did? Thanks!