Pucks in Rancor are 74-77. Korrigan in Boyahda are 72-75. I'd suggest skilling on Korrigan until the skillups start to slow down (assuming you can tell when they get slower, as slow as they already are) and then moving to Rancor. MNK mobs like mandies are best since they attack twice as often as other mobs, which not only gives you two chances to skillup per round but also two chances for Phalanx to reduce the damage. You might also want to use a
buckler type shield since they block most frequently of all the shield types, again giving you as many chances as possible to get a skillup to proc.