@jakemoran,
The chance of rolling
exactly five straight 1's then three numbers that are not 1's is:
(1/12)^5 (11/12)^3 = 3.095e-6
The chance of rolling five one's in any position is that value times 8!/5!/3! = 1.733e-4
The chance of getting any number (not just 1) is that value times 12 = .0021 or 0.21%.