Trouble running 3dClustSim and 3dttest++

Hi afni experts, afni newbie here. I am trying to run 3dClustsim on a dataset where I’m also using 3dttest++ to create functional overlays for a group analysis. I’m doing this because the false discovery rate is not working properly in my version of afni. To elaborate, the q value adjusts itself only to a point but after I raise the T-threshold slider past a certain point it stops adjusting itself. I was told to run 3dClustsim on my dataset to compensate for this, but I am unsure how to execute this in the terminal, and I could really use some help with working this out. Could someone please demonstrate how to accomplish this? Do I need to run 3dClustsim before or after 3dttest++, or run them simultaneously?