I use springs that normally come in a an 18T that hold the dogbones.
http://www2.towerhobbies.com/cgi-bin...?&I=LX2466&P=7
There's a link. That what I use on my G2R and it works great. I like it better than using spacers like fuel tubing or shims because they will give and allow the dogbone to move around if anything happens (but wont let it bounce and rattle all over the place).
BL Revo: CF G2R, LMT1940/7, 6S FP 30C Lipos, MMM, Hitec 5955TG
CRT .5: 7075 Ext Chassis, LMT1930/7, FP 25C 3S Lipos, MM