Firstly its not a bad decision depending on what you intend to do with the Sp 16. Let me try and help.:
1. You first have to insert your new USB drive into the SP 16 so it sets up the Toraiz and sub folders
2. Now plug the USB drive to your PC and transfer the samples to the Samples folder under the Toariz folder. Almost all LM samples are 24b 44.1 so they should be readable.
3. Plug the USB drive into the Toraiz and Viola - it should be visible.
are you able to see the external USB drive on the SP 16?