If you wanna run external spools and still using AMS Lite, this is a good solution to fit a bowden tube to the inlet and secured. I've been using this for quite a time so it should be good enough. Just click it onto the AMS Lite inlet and it takes 4mm tube. I print this adapter with TPU-95A, haven't try hard material like PLA or PETG, you can have a try if you want.

Orientation: Logo down
Material: TPU
Support: No