You will need two drill bits, sizes 11/64 and 3/16. Lets get started, here are the blades used

Start by using the 11/64 drill bit, carefully with your hand start twisting it in the blade mounting tab. A drill press can be used if available, but a hand drill is not recommended unless you take great care not to take too much material or drill at a different angle and offset the pitch. Take your time in this step and ensure that the drill bit is perpendicular to the mounting lug and not to the blade as shown below. The blade has the pitch set in relations to the lug. Once the hole is large enough, now work the 3/16 drill bit the same way, taking your time not to change the pitch angle or over enlarge the hole.

Test fit the blade on the head and if it's still tight, carefully work the drill some more taking a little more material off and test fitting again. Continue with this until the blades don't have to be forced on and the fit is too tight. Once happy with the fit, apply a light coat of thin CA to strengthen the area.

If you happen to enlarge the blade holes too much where the blades are very loose and has a lot of play, don't worry, this can be fixed quickly with a little medium CA and accelerator. Simply apply a little CA and "Kick it" with a little spray of accelerator. Take your time on this step and build up enough material by "layering" a few coats of medium CA and accelerator. Blade with built up CA shown.