I bought a 1913 Model T pick up in February and had it shipped to the UK. It arrived today. It's not entirely original, but it will suit me OK. It has lost the lid to the coil box during the journey. I can't remember if it sloped or was flat! It was dovetailed mahogany.
Does anyone have a lid? Or, perhaps a whole box? If there was a contemporary metal design, with an aperture for the switch gear, I would consider that instead.
You need to post which box you have. There were several different makers of the coil boxs and not all will interchange.
What is the name on the switch, also if original it may have non-standard coils I believe the standard coils started in 1914. RV Anderson would be the person in the know. Pictures are almost a must!