As others have mentioned there is the "spacer ring" which can bring up a world of hurt with your stud length, and there are the spacers which bolt on, using the existing studs, and have their own studs which you then use. Much safer; in my opinion the only way to go. The question for me is steel or billet aluminum. To my knowledge there are very few bolt on spacers that are made of steel. What are the cons of aluminum, other then the known bi-metal reaction. Are there any strenght issues with the billet high grade amuminum spacers?
why would you use larger spacers in the back? i would think i would want everything to be the same and i would add the same size spacers in the front.