Please, need some advice.

The plane is an experimental homebuilt with a
C-85 engine and 2 new factory overhauled Bendix S4LN-21 mags, each with
impulse couplings and to be timed at 30 & 28 degrees BTC.

Have been trying to install and time mags in acordance with TCM MSB94-8A.
Basically: Ignition wires disconnected and top plugs out of engine; then to
TDC on compression stroke, prop mounted degree wheel to 30 btc for left mag
after unloading the impulse coupling, red tooth of plastic gear positioned
in center of mag access hole (temporarily restrained so as not to move while
installing mag); same for right mag at 28 degrees; remove temp restrainer
plug; hook up "Inductor" (dual mag synchronizer with four phase audio
signal and two LED's); upon hookup, find LED's off and continuous tone which
means the points are open; then try to rotate mag to a position where
points are closed and LED's on........tried many, many times to get points
to open at specified timing BTC!

my problems a
1. Can't turn prop slow enough to get anything other than a very quick LEDs
blip-blip (on-off). I would have thought the points would be closed for a
longer duration..?
2. Can't get enough "travel" on rotating the mags.
3. Have never done a mag installation
before G.

Any help would be appreciated, Dick

PS-I have the Continental engine manual and read and reread the mag
installation section.