I can install the standard image from the openwrt page but that doesn't include the USB packages/etc. needed to get it my 4g dongle working and there isn't enough space to install all the packages. Are there any lite images/hints to get this up and running please?
I think the best way is to use the image builder. Any chance your modem is an Hilink one?
It's a telstra branded one I think is ZTE.
https://openwrt.org/toh/tp-link/tl-mr3020 -- 4/32 device -- not (yet) on "tiny" build from what I see.
I'd suggest adding a powered USB hub and using "extroot" on a USB drive to figure out exactly what you need and what the configuration would look like with the dongle. Then you can try to build a self-contained image (which may will mean dropping LuCI)
If you use the image builder I'm pretty sure you can fit all the packages on the image but there won't be space for anything else.
I managed to use the default image I just needed USB mode switch!
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