This is 10 amps max into a single battery. Connect at the fuse panel is fine. In fact if you have an open fuse position you can insert the wire right there.
Yes it is slightly better to have the controller close to the battery. However in this set up I doubt you will notice. You do not need anything more than #10 wire for 8 to 10 amps.
If you are installing the controller away from the battery to see the display just get a controller with no display or a remote. Basic $6 panel voltmeter (ebay) will tell where you are at.
Be aware some controllers need to be connected to the battery at all times when the solar is producing power. So if you disconnect the battery for service or storage you need to disconnect the source power from the controller first. Install instructions should cover this if it applies.