No you can not unless you change the frame from behind the gas tank back. Also the R3T has a 90 degree bevel gear box and because the swing arm is wider on the Standard it has a greater the 90 degree bevel gear box. You can however install a 200 mm and possibly a 210 mm tire on the R3T. with only 85 horse power at the rear you don't really need a fat tire. Unless your just wanting looks.
you can fit a 205 c/t w/out rubbing... I think a 210 c/t or m/t would rub.
And as Laraza said, why lower the handling ability for a fat tire that would barely be visible.