I asked questions here on painting my El Camino,got good advise.I've painted a few cars in the last 10 years and they looked good enough. So I get the car all prepped,shoot on the 2k promer.sand it down,clean the car several times and clean up the garage.Got the heat cranked up to 70 degrees,all ready to go. I decided on a black single stage urethane with a some flattner added.Not as flat as primer but semi gloss.Got paint , activator and reducer.The paint supplier says 4 parts paint,one part activator and one part reducer,apply two wet coats so it dries to an even semi gloss.A no brainer,I got my measuring cups and I 've done this before,right? Wrong!!! I spray the car one wet coat and it looks good with no runs or thin areas just a nice wet paint coat.Wait 15 minutes for the paint to flash while I mix more.Spray on the second coat with the same results as the first,leave the garage while the paint sets up. I go back out after an hour to inspect my fine job.What the fuck!!! there's a color variation,some areas look flatter than others,something happened. I check the paint paint and additives........Opps! Lots of activator but little reducer left.SHIT! Instead of 4 parts paint,one part activator and one part reducer, I mixed the reducer twice with no activator on the second coat!!!! Some much for paying attention to the labels. Anyways,the paint still dried hard but has some glossier and duller areas.The car sides aren't too noticable but the roof and hood look like crap.I got paint left so I masked off the car again,sanded the new paint,and tomorrow I'll spray the hood and roof. A lesson learned.