First, we simplify the given complex number.
$$\frac{i(-6+i)}{|3-4i|} = \frac{-6i+i^{2}}{\sqrt{3^{2}+(-4)^{2}}} = \frac{-1-6i}{5} = -\frac{1}{5} - \frac{6}{5}i$$

The real part of the complex number is $-\frac{1}{5}$, and the imaginary part is $-\frac{6}{5}$. The difference between the real part and the imaginary part is:
$$(-\frac{1}{5}) - (-\frac{6}{5}) = 1$$

Therefore, the correct answer is $\boxed{B}$.

This problem involves the algebraic form of complex numbers, their multiplication and division, and the concept of the modulus of a complex number. It is a basic problem that tests fundamental understanding of complex numbers.