Help! Creating rclone package in build directory?

Hello there, I have an RT3200 and am using a snapshot (OpenWrt SNAPSHOT r17471-b6cbbbb6ef). I am trying to create an rclone package for my router, but am strulling.

Can anyone advise as to the steps to build the rclone package?

I believe I need to download the source for hash : b6cbbbb6ef - how do do I do that?

I believe I need to amend feeds.conf to include the line:
src-git Rclone

Then what do I need to do to build the rclone package at that point?