Remember when using the PC and XMT, to ALWAYS take your time. It will take you HOURS not minutes to polish your truck. In your case, maybe days, depending on your PC skills.
Rule of thumb:
Don't use a lot of product. 2 dime-sized "blots" of product is enough.
Always take your time.
Apply pressure to the HEAD of the PC, while balancing the tail part. A good rule is to apply a lot of pressure until you don't see the head spinning any more, once you do this, gently let off. You need to apply a decent amount of pressure, and move the PC slowly. It takes time to break down the polish to remove surface defects.
Don't rush yourself. I would do maybe half the truck in one day, the other have another. Getting used to the PC can be troublesome unless you have good technique and know your products.
Always try and use the LEAST aggressive product/polish first. Sometimes the case may be where the swirls APPEAR deep, but actually XMT #1 or XMT #2 might to the trick, instead of using something more aggressive.
Remember to work the PC from side to side, and up and down on the same panel. If you want to get tricky, a quick pass from corner to corner works well too. Always overlap about an two inches or so.
Use blue painters tape to tape seals, chrome fixtures, emblems, etc.
I hope this helps shed some light.
Did you pick up a sealant or finishing glaze?