Without any rings on that contra-piston, you’ll never get this to run.
I don’t think straight diesel fuel will get you there either.
The smaller diesel model engines don’t have rings, but those small pistons are lapped to size, and the cylinder bores have the slightest bit of taper. At tdc, the piston may actually feel stuck before the first few break in runs.
I always ran all of mine on equal parts of ether, kerosene, and castor oil.
Regular “starting fluid” ether works fine, but be sure to read the label, as not all starting fluids are the same. It should contain at least 70% ether. They recommend 2% of some kind of “stabilizer” to the mix also, but it’s not needed, and good luck finding it anyway.
At room temperature it should fire on compression alone, but warming the cylinder will help. My Mills diesel engines run cool, slow, and amazing quiet, but the Russian diesel i have will burn your face off, and it screams like a nitro.