Hmmmm. Risk vs reward....
Option 1 - I give way to the bigger vehicle just in case he doesn't give way to me.....possible outcomes - 1 minute of my 5,6,7,8 hour journey waiting if he doesn't give way to me or ......1 minute of my journey if he does give way then I have to take off again.
Option 2 - I don't give way ......possible outcomes - he gives way and I haven't wasted a minute of my life giving way to him......or he doesn't give way either and we see how wide the bridge really is.........
I think I know which one I would choose regardless of who had legal right of way.
Peter