Mine was horizontal and I had to move it up a notch. When I told my dealer he said they had already done it as part of the PDI.
I remember some years back in the old motorcycle magazines there was an article on the ideal footrest position.
The general concencus was vertically in line with the nose of the seat was the ideal position.
On the classic 350 the pegs are forward of the seat nose which means the angle of your foot is flatter requiring a bit more room especially with boots.
It's easy to move the frame rail just loosen off the front engine through bolt then remove the rear bolt on the frame rail on that side.
Remove the lever pinch bolt and mark the lever position relative to the spindle/splines.
You then just push/wiggle the rear of the frame down and this allows enough room to pull off the lever and move it.
Nothing falls off or requires realigning app 15 mins in time.