The Sorted-List algorithm for the simulation of a 3D-GRFIM has been implemented in C++ and executed in DIRAC Iberian grid in order to obtain distributions of size and duration of magnetization avalanches. We have performed maximum-likelihood estimations of the power-law exponents. We have obtained 2D-exponent maps by scanning the upper and lower bounds of the distribution. We have used the maps to compare the behaviour of two different methods for classifying percolating avalanches and evaluate the dependence of the exponent with the disorder parameter R and the size of the lattice L.