4holer; an alternative and many say more accurate and sensitive way to set the pitch then the cheezy factory supplied mickey mouse protractor is to use a cheap laser level. Forget the level part, what we want is the laser, that we can clamp to the prop blade using the level's straight edge, the exact same way every time. I paid $20.00 at Harbor Freight for one. Then a simple jig fabbed from scrap in the shop in about 10 minutes gave me a way to consistently locate the level on the prop blade in the same way every time. Actual levelness does not matter. Chock your wheels fore and aft, be inside a hangar (out of the wind of course, more importantly you need to see the red laser dot, so dark enough), and make a mark on the floor where the dot hits. Then rotate the prop 180 degrees, using another simple jury rigged jig on the opposite blade, to hold that blade at the same exact height as the opposite blade, so the prop ends up in the same location rotation wise, just now with the other blade having the laser on it. Adjust that blade so the dot is at the same place as the first. Take it outside and run it up, in your case you need to reduce the pitch, so simple trial and error will quickly determine how much dot movement on the floor correlates to pitch change/static RPM change.
I recently set up a 79" LUGA prop this way, with no idea of the desired actual pitch (nor did I care, as I would go by the static RPM anyway) as measured in degrees. It took a total of about 2 hours, including the simple jigs, after first eyeballing what seemed to about the right pitch, static testing, then in 3 or 4 adjustments, "sneaking up" on the exact desired static RPM I wanted. I had it down the last few adjustments to less then 10 minutes between changes. You will quickly see how much dot movement on the floor changes the static runup RPM. The benefit of this method is you have a much longer moment arm, (a good a term as any) as in very small changes of the blade angle, result in major changes in how the dot hits the floor, the end result being both blades will end up being dead nuts at the same angle. WHAT that angle is in degrees is immaterial, who cares! It's your rpm in use that counts..... I now also have a nifty laser level for other shop uses.
FWIW: with my prop blades/spinner height about 65" off the hangar floor, moving the dot about an inch on the floor, changed the static RPM 200-300. You will see the dot move, before your eyeballs see the prop move in the hub, that 65" moment arm amplifies any movement!