To run an ARB snorkel with an exo @ the A-pillar, you'd probably need to buy yourself a new fender, and redrill the entry hole shifted towards the front of the jeep the width of the tube you are using added to distance from the tube to the actual A-pillar.
So if you're using 1.75" tube, and that tube is say, .75" away from the a-pillar, you'd shift the entry hole for the snorkel 2.5" forward on the fender. A-piller exo tube would need to be as close to the angle of the actual sheetmetal a-pillar for this to work, but I guess I'm assuming that's what most do anyways.
Once that's done, you can weld a small tab onto the A-pillar cage tube that would engage the upper snorkel body mount that used to be attached to the A-pillar.
Measure 3 times, and cut once and you should have a snorkel that mounts up just as cleanly with maybe a bit of the snorkel coming above the level of the fender if viewed from the passenger side fender, but the snorkel snout that goes inside the fender should have no interference from the inner fender, and other than maybe needing to trim the tube that goes to the front of the airbox, you shouldn't have any changes.
(This is all assuming there isn't a horizontal A-pillar to stinger/bumper tube in the way, and that it's been routed low or outboard a bit to accomodate a snorkel)