1) Others' comments are correct. Actually, this would suggest that you DO have the original motor. Every state is different, but I would think that if in "modern times" the engine was swapped, the Title would be changed to the VIN and not the new engine number.
2) I'd go electric unless you really want to go 100% stock on your truck. Or if you don't drive in the rain. That's personal preference.
6) Is it really sticking, or are you just kicking it out of fast idle with the throttle foot-stab?
