After completing the riveting of the top skin I noticed the wing walk doubler is between the skin and the main wing spar. After checking with vans and talking to Greg Hughes, it was determined that this must be fixed. I began drilling out rivets. I'm hoping I won't have to drill out many of the countersink rivets but I know I will have to drill out some of them. The goal is to expose the wing walk doubler to the point I can sand down the leading edge a few thousandths.