ALCO Featherweight valve timing

Hello everyone.
I’m reasonably new to the forum and totally new to stationary engines so please forgive the naivety and lack of knowledge.
I recently purchased an Alco Featherweight which I believe is a rebranded JAP engine. To date I’ve not been able to get it going and setting the timing seems impossible. It’s so frustrating as this seems so simple compared to our previous work on engines (mostly motorcycles from the 60’s).

There is a BTH K1 magneto fitted, and it has a reasonably good spark.

The cam shaft gear has a clear circle mark, but the crankshaft gear’s mark falls below a tooth and not in a valley as I would have expected for meshing. The mark on the crankshaft gear is more a symbol rather than a circle.

Is there a specific position for the crankshaft gear as there are in my opinion at least four ways it could be placed? When at TDC the keyway on the crankshaft points vertically up but the gear could be as I’ve said put into different positions.

As for alignment we’ve tried every permutation but obviously not the right one.
Does anyone have an image/photograph/diagram anything that could point me in the right direction of the correct alignment?
Any help much appreciated.