Learning Bayes statistics from Allen Downey's Think Bayes

There are three dice, 6-sided, 8-sided and 12-sided. A randomly chosen dice is rolled and the outcome is "1". What's the probability it was the 6-sided dice?

Is it correct to setup the sample space made of 26 outcomes like so?

outcomes from 6-sided dice: [ 1 2 3 4 5 6
outcomes from 8-sided dice:   1 2 3 4 5 6 7 8
outcomes from 8-sided dice:   1 2 3 4 5 6 7 8 9 10 11 12 ]

Or is it just [1 2 3 4 5 6 7 8 9 10 11 12 ] ?

The prior is 1/3, the likelihood P(rolled-1|6-sided) is 1/6, but what is probability of evidence P(rolled-1)? Is it 3/26? Or 1/12?

I'm not getting the correct result using either.