Been trying to locate information on the proper Throttle return spring setup for a 68 Firebird 400 Ho ! Can someone give some feedback on what determined what color was used ? Example Blue or Yellow and did it use two springs to return the throttle ? or one ? .I attempted a forum search to locate information on about the springs but was unsuccessful. Also were the Original retaining bolt's ( for the oil filter adapter to block) a hex headed bolt ? or did they use the 12 point headed bolts like the fuel pump used ? Trying to put back together a 68 HO Coupe I purchased as a basket case Thanks in advance