LEDE on a AFOUNDRY (how to install USB modem)

Hi everybody,

I am quite new to LEDE, so if my question is redundant, please give me a hint, where to look.

I have an AFOUNDRY running LEDE snapshot, r5039-b73986a and I am looking for information on how to set up the router for an Internet access via a USB (eg LTE) stick.

I found a manual under medium(.)com, requiring eg kmod-ii, kmod-usb-net, etc. but I cannot find these packages via "opkg list" .

Is there a problem with my distfeeds or can anyone tell me a solution to set up this box in the way I need it?

Thanx in advance,

Best regards