i don't think there is a front or back on that intake. edelbrock states zero degree carb pad angle so what difference would it make? there aren't any vacuum or water port points for reference. can you imagine how screwed up that would be with a 4150 style carb with the driveline in it's correct location (3 degrees down toward the rear is normal)? if you had a car that could produce any kind of g-force fuel would slosh out the primary boosters and starve secondary. design float level would be screwed up. but, there are tapered carb spacers out there or one could be simply made from a spacer if someone had access to a mill.