Welcome...
my husband has a VTX 1300 s....and he drags his floorboard too quite often without even leaning very much. Seems to me the VTX does hit long before I do on my C50.
I looked for "extenders"..but couldnt figure out what you meant?
Under his footboards are small knobs that have been hitting the road and are scarred....is that what you meant? I think that would be called a telltale....and they are obviously what hits.
I dont think you would want to grind those off because then the whole outer footboard edge would hit the asphalt with a lot more drag... and that might dig in and upset your line rather than just give you a warning....?
Annie