Since I recently finished my Ghaz, I was looking into his rules a bit, and saw that Makari has a 3'' +6 feel no pain aura.
Reading the Painboy I see he has basically the same hability, but affects slightly different units.
Do these stack? IF you suffer a wound and you are in range and a valid target for both abilities, you can roll
D6 twice or only once?
In previous editions it would reference the "feel no pain" general rule, and you where able to do only roll
fnp once despite how many abilities granted you the rule. These do not say that you cant roll it more than once since they are different auras and abilities.
For comparison, Ork repair abilities do specify that you can only do 1 repair ability per unit per turn, even if there are multiple sources of repairs from different abilities (grot oilers, meks, character mek, unit abilities).