Hello Brian and Danny,
Yes the GT3 is clear coated and it had very little swirling in the paint except towards the rear of the car near the fin. Those will be tricky to remove because of the tight spaces which makes me wonder how they got there in the first place.
I'll try to answer both of your questions about polishing as best I can. First I have no idea what condition your paint is in so I will assume that they are both in fair condition, meaning that they are slightly oxidized, minor to medium surface scratches and perhaps an uneven gloss or shine.
With the above hypothetical diagnosis I would of course start off with the washing and cleaning of the wheels, wheel wells, tires and body. This is also where I attempt to clean as much of the vehicles molding, lenses, door jams and nooks and crannies as possible. I keep handy several soft to medium bristle brushes, a can of WD40 and some tar/wax remover. I picked up a clients Ferrari 550 yesterday at the Ferrari dealer to drive it back to his house only to find that some #@%! detailed it! There is wax residue in the moldings, the lense lettering and emblems so I will need to go through each one with my tar/wax remover, toothpicks and sable paint brushes to gently loosen and remove the residue.
This stage should take at least an hour or more. I would then clay the surface just after the final rinse but before the final drying. This way you safe some time plus you also save your QD. I always use an electric leaf blower when I dry, starting from the top and working my way down. I don't seek to completely dry the car but rather to remove the standing water in areas like the side view mirrors, headlights, door jams and body seams. Oh yeah, about the door jams- Porsche mechanics are notorius for really laying on the grease in these areas and this in turn collects grime and gives the car a really unpleasant look as you open the doors so what I do is while I am washing the car is spray a water based degreaser, like Simple Green, into these areas, close the doors and wash the car as normal. The water, especially when rinsing, flows through these areas and gets rid of a great deal of this EXCESS grease. I like door jams that are clean and polsihed. If any remains I'll remove it by hand in the detailing stage.
So now comes perhaps the most important stage in the whole detailing process, the prepping or cleaning stage. If your paint is as I assume and you own or have access to an orbital, whether it be a Cyclo or a PC, I would first tackle the more obvious scratches and blemishes using a medium aggressive product like Meguiars DACP and an "orange" pad or the green pads if using a Cyclo. Since the Cyclo costs a bit more I'll just assume that most folks are using the PC. The "orange" pad is great and if used properly can cut out one or two buffing stages. One can go directly from the cleaning step to the polishing step or to the finishing step depending on the paints condition.
If the paint is not all that bad then I would use Hi-Temps Light Cut Leveler. Thsi product is not as aggressive as DACP but it does clean th epaint, removes swirls and adds nice color. Both products set up the surface well for AIO. I would honestly say though that if I were doing your cars I would hit them first with the orange pad, DACP and then the Light Cut with a polishing pad. I would then give two coats by hand with the AIO then finish out with UPP and 25 hours later top that with Trade Secret.
For a quicker detail and real nice results you could use Vanilla Moose right after the DACP step and then top the VM with Trade Secret or P21S.
Finish out your detail with polsihing the wheels, dressing out the tires, the trim, windows and any chrome or aluminum. I usually do all this while the UPP is setting up.
Well I know this does not cover every aspect of detailing your car but it is a general going over and I hope it helps. If you need some more info or details about a certain area please e-mail or PM me.
Happy Detailing,
Anthony