Drilling out the old rivets yous as bigger drill bit as you can to just dril the tops off the rivets ,and then just tap them through and out of the holes ,with a dot punch , dont yous same sise drill to try to drill them out you will Elongate the holes for the rivets , and wont get a tight fit with the new rivets ,
Drilling CF , go and buy a new drill peace !!!!
Mark holes ,have drill set at its farstest speed , find rownded peace of wood to push end cap onto wen drilling it , Old log eney theing just to serport it and stop it from flexing while you drill it ,.