Terry is correct: there's already a bleed hole in the damping rod, so drilling a bleed hole in the valve will reduce rebound damping, causing the front to wallow. Also, drilling valves after they've been assembled risks damaging the shims (which will then fail to work as they should because they're extreme precision parts), and drilling after assembly is poor practice with regard to cleanliness (suspension damping components need to be meticulously clean).
Michael, I believe that the 5W Racetech oil required (per the Racetech spring rate/product recommendation calculator) has a viscosity somewhere around 16 to 18 cSt @ 40'C. The oil "weight" doesn't mean much because you can get fork oils that are rated as "5W" that have a viscosity range anywhere between ~10 cSt @ 40'C to ~25 cSt @ 40'C. Depending on which "5W fork oil" you get, the suspension could be far too soft, far too hard, or anywhere in between. So, always look at the viscosity. If it isn't in the correct range, grab a bottle that does have the correct viscosity (which could be 2.5W, 7W, or even 10W, depending on which brand it is). Also, other properties, such as cavitation resistance are important, so you may want to spend a few dollars more to get a better quality oil.