Jeremy,
I have a 59 that is mostly orig.6cyl. I kept it that way because everyone else did the v8 swap.
I see that what you have is really not much of an original truck. It's yours so do what you want, when it's driving down the street 98% of the people that see it will only say wow, what a nice old truck. They have no idea what motor is in it ,or what motor is suposed to be in it.
My suggestion would be a 4.3 chevy v6 they have over 200 horsepower, more than enough to do what you want.An automatic trans with overdrive, upgrade the brakes and steeering/rear end and you will be set.
Good luck, explore your options but remember it's your truck, not everybody elses.
