I couldn't get comfortable until I read on about someone doing what I did here. I rest my heels on the board and the bottoms of my feet on the pegs works very well I am 6'1 with a mustang seat.
I do the same, but I I agree with Irishman, the right is less comfortable than the left, mainly because of the brake pedal. For me, it's due to my seat, which pushes me slightly forward, forcing me to spread my legs to clear that damned wide tank.
As far as spacers, my local ACE hardware stores all carry an assortment of chrome spacers, from 1/4" to almost 3". They're not cheap, from $4.50 to about $8.00 each, but still easier and cheaper than most other solutions. I used them to mount my saddlebag brackets. The quality of the chrome is really good too.