I am using the pacesetters. I have a two inch set back plate from transadapt and I moved the frame mounts back a hole. My number two tube hits on the passenger side but with some tweaking (I havent cut or hammered) they will fit. I do have solid mounts though so I dont have to worry about the engine torquing and banging the tube on the frame.
As far as how far back my engine is, I wouldn't recommend it unless you want to "rework" your firewall.