grind them off. plenty of guys have ground them, polished them or painted them and they have come out decent looking.
Low Rider Tommy at hondachopper.com and cycle exchange at cyclexchange.net both have them but they are more for the chopper crowd. Too expensive for something you can just bolt a plate to to hide if you ask me.
also do a search at SOHC4.us for a goldwing cover plate that hides the cb750 bar mounts
I did sort of the same thing but instead of a mill, I used a sanding disk and my precision set of $2 Harbor Freight files. This is on a CB400F, so the casting may be different but you get the idea.
The tapped holes for the handlebar mounts go all the way through, so I used those as a starting point for those slots. I could probably whittle away some more material, but I'll leave it like this and make sure it doesn't crack on me first.
If you have an early CB750, the offset and spacing is the same as CB450/CB500t. The CB450/CB500t handlebars are rubber isolated so there is only one hole left when you unbolt the risers. You can grind down the post a little if you want a cleaner look or leave as-is. I'll see if I can get pics of mine.
Proteal welded up the casting holes on his before grinding it down.
doesnt everybike have the brake on the left? my throttlerolls forward too. i dont know whats up with that. at somepoint ill have to explain it to you. how i did it. but yeas, its retarded. i havent figured it out yet exactly.
...and the tach needle rolls couter-clockwise. somehow you flipped the image. it used to happen all the time when i worked for the magazine, sometimes it was even intentional to get a better composition, so you can run with that.