You have to have a tach to do it properly. With the expense of a prop, I think the 40 or 50 bucks on a tach would be worth it. Sometimes they get put on sale if you'll watch. Or like said before...check ebay.
After you get the tach...you need an average load on the toon. Check your WOT reading. Be sure its not a light load...or really heavy load as both will mess you up when propping.
Whatever reading you get...do the math and see how many rpms you have to move to get to your desired rpm.
IE...if you are running 4800 rpm now...and your goal is 6000 (as per manufactuer recommendations)...that is 1200 rpm. It 1" of pitch up or down to move 200 rpms. So if you are running a 17" pitch prop now...an 11" pitch will get you to where you want to be....thats just an example.
Without tach reading you won't be able to do it right. Do not just use ear...that 60 will sound different and be at a different height than it was on the tracker.
Remember too...I'm sure you know already...higher pitch gives you less rpms but more speed...lower pitch gives you higher rpms, less speed, and better hole shot....all that being said...thats ONLY in the manufactuer rated rpm. Too much pitch is what you have now...a lugging situation which is worse than anything else. Good luck!
"But if serving the Lord seems undesirable to you, then choose for yourselves this day whom you will serve, whether the gods your ancestors served beyond the Euphrates, or the gods of the Amorites, in whose land you are living. But as for me and my household, we will serve the Lord.” Joshua 25:15