▁closest ▁to ▁Memorial ▁Day . ▁Thus ▁for ▁more ▁than ▁a ▁de cade , ▁the ▁two ▁races ▁were ▁held ▁on ▁different ▁days ▁of ▁the ▁week . ▁This ▁prompt ed ▁a ▁hand ful ▁of ▁NAS C AR ▁regular s ▁to ▁attempt ▁to ▁race ▁in ▁the ▁Ind y ▁ 5 0 0 . ▁On ▁a ▁few ▁occasions , ▁drivers ▁were ▁able ▁to ▁" cross - over " ▁and ▁comp ete ▁in ▁both ▁events , ▁or ▁skip ▁the ▁race ▁at ▁Charlotte ▁in ▁favor ▁of ▁Ind y . ▁ ▁The ▁NAS C AR ▁points ▁system ▁util ized ▁at ▁the ▁time , ▁as ▁well ▁as ▁the ▁structure ▁of ▁the ▁schedule ▁itself , ▁differ ed ▁substantial ly ▁from ▁modern ▁times . ▁The ▁system ▁was ▁much ▁more ▁forg iving ▁of ▁drivers ▁who ▁missed ▁a ▁single ▁race , ▁which ▁is ▁why ▁some ▁drivers ▁chose ▁to ▁skip ▁Charlotte ▁altogether . ▁ ▁In ▁ 1 9 7 1 , ▁the ▁Un iform ▁Monday ▁Hol iday ▁Act ▁took ▁effect , ▁and ▁began ▁to ▁alter ▁the ▁respective ▁sched ules ▁for ▁the ▁races . ▁Starting ▁in ▁ 1 9 7 4 , ▁the ▁Ind y ▁ 5 0 0 ▁was ▁perman ently ▁moved ▁to ▁the ▁Sunday ▁of ▁Memorial ▁Day ▁week end . ▁Thus ▁from ▁ 1 9 7 4 ▁to ▁ 1 9 9 2 , ▁the ▁races ▁were ▁scheduled ▁for ▁the ▁same ▁day , ▁and ▁at ▁roughly ▁the ▁same ▁starting ▁time . ▁Therefore , ▁drivers ▁were ▁not ▁able ▁to ▁comp ete ▁in ▁both ▁events . ▁Furthermore , ▁in ▁ 1 9 7 5 , ▁the ▁NAS