“[...] Apparently the Dangerous Clown pardoned this jewel of Law Enforcement. [...]”
Yes, true. Inadvertantly he may have caused Arpaio more trouble. Having accepted the pardon (as I believe is the case) Arpaio cannot appeal the conviction. This does not remove the conviction from his record and he is still a felon. Under Arizona law, a felon who has served his or her entire sentence can vote again, but there may be other steps necessary for him to restore his right to own firearms, which no doubt he does.
But in any case, he has to disclose the felony conviction on any application he makes in the future.