Scott: Your comment interests and puzzles me?
May I ask if you actually measured the ODs of the tubes with a caliper or a mike or based your comment on the drill size recommendations that came with the kits.
CSUSA recommends 10.5mm and 12.5mm drill bits for the Jr. Gent II kit while Rockler recommends the 13/32" and the 31/64" bits. Both sets of recommendations will probably work; but the Rockler bit recommendations will produce holes that are extremely tight. IIRC, CSUSA used to recommend the bite sizes quoted on the Rockler web site when the kit first came out; but revised their recommendation when they realized it was not the best.
I would be willing to bet that if you actually measure the tubes, you would find out they are the same size in both kits. If not, then Rockler has somehow messed up your order.......maybe included the wrong tubes with the kit. It has happened before!!:wink: