If the rod is fouling the frame to the extent that it is hindering movement are you sure you'v got the R1 bit lined up correctly dot vs gap and also is it the right way round?
Even if you have to remove the left footrest it's only 3 bolts.
I had it the right way round and reasonably sure it was lined up with the dot. The issue I had was trying to figure out the gear lever position and tying to stop it even touching the frame
Just been looking at Karlos post when it hit me, I forgot about the removable allen bolts in the ball joints. So worst case if my little adapter idea fails I can fall back on the useal method and when it comes to removing the R1 arm when changing the front sprocket I can just undue the said allen bolt etc.
now you know there are different early R1 arms. Mine doesn't have an allen bolt through, it has a large peened rivet type thing. I reckon there were 3 different versions up to 01. The 98 fitted clamp inwards and the 99 clamp outwards so the fouling may differ dependent on which you have.