I do these peelers all the time,I think the two main causes are #1 the sun and #2 thin clear.
You hve a few options first off its hard to tell from just a pic but the cheapest and fastest way is to only do the top surfaces (that Irock decal might be a little pricey) and from the molding down looks pretty good.
so start with a razor scraper and carefully scrape ALL the clear of,if there are stubburnd spots sand those with 320 getting the clear offdone this way theres no need for a sealer just base it and clear it,that little strip between the T-top and the rear glass is ez and the deck is pretty short so that wont take much time but the hood is a different story that might take a while with 320...basicly you dont have to sand ALL the clear off just sand it until it starts feathering nicely.
if you have a lot of dents or dings and if the clear isnt cooperating sanding with 180 is much faster but you'll have to seal it with a good epoxy(SPI reduced about 20-30 % works great)once the top surfaces have been epoxied then sand with 320 If you want to paint the whole car all it needs is 320 and shoot no need for any sealer of any sort on the sides unless you do a lot of dent and ding work on them.
If you use a razor scraper BE CAREFULL not to gouge the surface or or all bets are off... theres a few tricks to using the scraper like honing the new blade on glass and good quality blades ...I use them all the time without any gouges but it takes some experiance and technique I find most guys need help using razor blades so try it in a few spots and see if its working for you but for heavens sake dont keep going and gouge or scratch up the whole car then you'll be in trouble,so be very careful and if you have any question just ask, theres some other little tricks too..