We just purchased a 1955 3100, 1st series. There is no motor, but she used to have a 6 cylinder, the 4-speed

tranny is setting in the bed. The truck is in great shape overall. We would like to get some suggestions on where to go from here. Should I find a good six and install that, or should we upgrade to a V8.
We are leaning on finding a good six and tranny combo already to go and then install that.
Any help would be appreciated.
Kevin & Cindy