These are pseudo splits and are polished (or rather diamondcut) and laquered. All you do is wet and dry the laquer off, 800 grit and plenty of soap in the water, use hairy lipsquid for this. Then, when you can see that the laquer is gone and you're down to bare ally, clean them off and inspect the pitted areas. Some may be deeper than others so you are going to have to wet and dry these areas further, try and use longer strokes than the immediate area of the pitting, this will help avoid putting 'dips' in the surface. Next step is to use some G3 cutting compound, a lot of people may reccomend missing this step, but it will help remove any deeper scratches put in when wet and drying. Clean the wheels off again and then set to with the Metal polish, I use Autoglym stuff, but brasso etc will do the job just as well. Once you can see your face in the rims you'll need to use some panel wipe and clean any polish residue off your wheels, do a thourough job of this as the next steps will not work otherwise. Take a red Scotchbrite pad and rub down the painted areas of your wheels, we arent trying to break through the paint here, merely 'keying' the surface ready for the new laquer. Once you have got rid of ALL shinyness on the paintwork you need to give them a darned good wash off with hot non soapy water and dry them thouroughly with a paint stripper gun or similar, take care not to linger in one spot too long or you'll bubble the paint and have to do more work. then you need to mask off the back sections of the wheels. This prevents unwanted laquer getting on the insides of the wheels and then peeling off and looking unsightly in the future. I used Halfords clear coat aerosols to protect wheel rims as it goes on nice and evenly and dries quite fast too. Just apply the laquer lightly at 1st and get the 1st few coats on the lips before you do the centres letting each coat dry for around 20 mins in between, then do the whole wheel a coat at a time and turning the wheel as often as needed in order to ensure that you cover all visible parts of the wheel........allow 12 hrs drying in the house and then refit your tyres and get em back on....good as new!!