The title says it all, anyone know where I can get one? Or if I can modify a similar switch to work with the 10 wires that need to come out of the CT2's?

 from near Salisbury, UK.

Do you have a budget?

I'd be pretty certain that other switches can be modified, although the work needed depends on what parts you have to start with.

The CT1C and CT3 use the same switch.

I do not have a budget and I only have a main switch from an AT2 (see picture) that I'm fairly certain cannot be modified. I've looked all over eBay for the exact part number matching the CT2 (and also matching other bikes like you've mentioned) and have not found one.

I'd just like some way to wire up the bike from the ignition to work with all factory electrical parts, not really concerned about budget or effort at this point.

What part of the world are you located in?
 

You could buy this and sell on the clocks.

1970 VINTAGE YAMAHA CT1 INSTRUMENT CLUSTER SPEEDO TACH IGNITION BRACKET | eBay

Do the same with this, but maybe switch the barrel/lock from your AT?

YAMAHA AT1 125 CT1 175 SPEEDO SPEEDOMETER TACHOMETER GAUGE CLUSTER & BRACKET OEM | eBay

Thank you. I did not think of looking for the whole set. This will work great.

Excellent.

I'm pretty sure that, as a set, the clocks fit the CT1 and AT1, so sell these on (they aren't the same as those on your CT2) and maybe get all of your money back!

Individually, the speedo and bracket fit the AT1, CT1, DT1 (not 1968) and RT1, so maybe best to split them and sell individually.