After an couple hours of research on a few sites I figured it out.
All the Porter Cable models are the same. The different model numbers are specific to the attachments and counter weights. The body of the units are are the same.
7424 (what most on this board use) This is actually a 5" polisher therfore, it comes with a 5" counter weight. The polishing pad that is comes with is so light the 5" counter weight can be used eventhough it is 6" foam pad.
7335 Same base unit as above but comes with a 5"sander attachment with a 5" counter weight
7336 Same base unit as above but comes with a 6" sander attachment with a 6" counter weight
Now for the unit Jason got, from
Griot's Garage
it is the same as
97355 or
97366
These units come with a few more attachments for sanding and a vacuum tube, which is why they cost more. But most of us will not need these attachments since we are using the units as a polisher and not a sander. This would be an option if you like the case or plan to do some sanding.
All these units still need the CMA kit. It goes for $59.99
here, because none of these units will include a velco backing plate which is necessary for polishing.
So in conclusion, what I have found is that you should get the 7336 with the CMA kit and you'll be set. The reason is the 7336 is cheaper and more readily available at a local Lowe's for $109. There is nothing wrong with the 7424 but it only comes with a 5"counter weight. So remember that you need to get the 6" counter weight. But then again it is only $2.00 The price difference over all with shipping through coastaltool.com, is around $5.00. So really no big deal. It just depends how anxious you are to get one.
If you want more information on counter weight check it out
here.
This is a follow up. I called Lowe's and confirmed the price on PC 7336. They told me it is $109. I took this price to Home Depot and they special ordered for me. They even beat the price. So the final price out the door was $106.19. It does take about 3 weeks so it just depends how much of a hurry you are to get the unit.
These are the links for places to get the polisher online.
Amazon
Walmart Probably model 7335 but not specified.
Coastal tools