The instruction should tell you how far from the leading edge the CG location is, I can't tell you where it is though, low wing airplanes should be balanced upside down (pendulum effect makes the airplane more stable as opposed to doing it the other way around), two persons do a better job than one would, hold the airplane by the wingtips at the (extended imaginary line) CG location, use just one finger in perpendicular fashion to the fuselage, a more accurate method can be achieved by building a CG locating stand, but by no means the finger method will ever by outdated, or you can buy a CG locator which is available in the market place.
If the tail goes down, add necessary nose weight as far forward as possible (I like to melt lead in a tin can, let it cool down, cut the can away, drill holes in the lead ballast so it can be held by the engine mounting bolts, but first mount the engine, and use locknuts with rubber inserts, only after the engine is well mounted and secure, the lead ballast is positioned in place and again securely tightened with locknuts and washers, apply Goop or equivalent to the bolt ends, as lead weight being soft, it they vibrate will come loose).
I would look for an airplane that when being balanced hangs nose down about 20 degress or so and even 30 is ok, late you can adjust the balance as you see fit, by adding or removing lead.