I just received my thickness guage in the mail yesterday from harbor frieght. Took about 10 days on regular shipping ok to me. My question is I am doing my f-150 restortaion of the paint, took it out today calibrate it and took some readings on the clear coat, reading were on hood where not touched yet read 4.9- 4.7 mils. How much is to much to take off from wetsanding that I will cut past the clear and into the basecoat? I did some areas already before I bought the instrument and the readings are 4.5-3.9 etc. I did my whole roof and checked some areas and the reading were 1.9-1.7-1.6 mils. Now on these readings how much more can I go before I go to deep. The roof I have done some polishing on it to bring back the finish w/ xmt 3/ merzerna p106ff also ok results but need to bring out some more. I need some information on this so I can continue with this project, I'm planning on sanding the whole truck for orange peel alson amoung scratches. The guage is really nice though not off but 1-2 mils on some areas.:righton: