Ok gang...problem solved. Thanks to a local injection pump rebuild shop, I was able to find out the information I needed. There is indeed a relationship between the hash marks on the geared rod and the other components. Each hash mark on the geared rod lines up with the center of each injection port. Once this is lined up, the geared hub is inserted into the cylinder. Note that on the bottom of the geared hub (the end opposite the gear itself) there is a very tiny indention. It almost looks like a flaw in the material and if you weren't looking for it you probably wouldn't pay it any attention. When inserting the geared hub, line the indention up with the hash marks on the geared rod and slide it in place so that the gear and geared rod engage. Next, insert the plunger. The plunger has a lobe on it which will lock it in place once its inserted into the geared hub. Note that on the lobe of the plunger there are some markings. numbers on one side, and something that looks similar to a target on the other side. When inserting the plunger, the side if the lobe with the "target" faces the geared rod. Other than these specifics, the pump goes together pretty much as the parts breakdown diagram which can be found on the New Holland web site. These are not difficult pumps to rebuild. Anyone with a little mechanical knowledge shouldn't have any problems. I can't advise anything on the cost of individual parts but the shop that gave me the specifics on the pump said they charge about $325 for a rebuild.