#1
Police truck has some very similar lines to the cramps song human fly in my opinion. Not all the song, but a few lines

They're similar, it may not be a rip off but the influence is there
#3
Its like rockabilly and psychobilly. You're gonna get alot of the same riffs and chord progressions because that's what gives those styles thier distinctive sound.
He who acts, conquers.Nashvillepunk.org

I'm old, I'm tired, and I have acid reflux. So don't mess with me.