One of the 1st things you need to do is put your detective hat on and determine what you have in your truck now. I bought my 54 GMC 100 truck 2+ years ago and the list of non original parts I've discovered keeps growing. My truck no longer has the original engine, transmission, and drive shaft, emblems. The point is before you assume it's all original verify it or you will end up ordering the wrong parts.
Jim