To solve this expression, we will first convert all the mixed numbers to improper fractions.

8 7/12 = (8 12 + 7) / 12 = 103 / 12
2 17/36 = (2 36 + 17) / 36 = 89 / 36
4 1/3 = (4 * 3 + 1) / 3 = 13 / 3

Now, substitute the improper fractions back into the expression:

(103/12 - 89/36) * 2.7 - 13/3 / 0.65

(103/12 - 89/36) = (1033 - 89) / 123 = (309 - 89) / 36 = 220 / 36 = 55/9

Now the expression becomes:

(55/9) * 2.7 - 13/3 / 0.65

Now, we will simplify multiplication and division:

(55/9) 2.7 = 148.5 / 9 = 16.5
13/3 / 0.65 = 13/3 1/0.65 = 13/1 * 1/0.65 = 13/0.65 = 20

Now the expression becomes:

16.5 - 20 = -3.5

Therefore, the answer is -3.5.