Hi Gang,
Thanks for the update. As I see it, currently I have three options (though I'm sure this will change as this topic evolves)

I was able to use the ACF option in afni_proc.py by passing it through the 3dBlurToFWHM options for a resting state analysis. In regards to final cluster size (3dClustSim simulation) is it better to

a) estimate to ACF parameters (3dFWHMx) by calculating residuals from the 3dMVM output stats (or in one analysis I can run 3dttest++), one for each comparison.

b) estimate the 3dclustsim -acf parameters from the errts.fanaticor+orig file (technically not noise since its resting state output) using 3dFWHMx -acf?

c) estimate the 3dclustsim -acf parameters from all.runs -errts.fanaticor+orig which should represent first level residuals if it is too difficult to obtain from 3dMVM?

I guess I am not sure if estimates from input files are valid for clusterwise thresholding or if it HAS to be from the output stats files (ie 3dMVM or 3dttest++ residuals).

Thanks,
Ajay