I am trying to determine why I have a gap between the last washer on the cam snout and the spacer in front of the fuel pump eccentric. I have installed the beveled spacer, retaining plate, timing gear, fuel pump eccentric, spacer, washer, and bolt, in that order.

Soffian Adam
Jamestown, NY
59 F100, 55 Club sedan

The spacer with the key slot replaces the fuel pump concentric counterweight.  Either of those went behind the fuel pump concentric but only one or the other is used.  The thicker non slotted spacer goes in front of the fuel pump concentric and then the bolt and washer to hold everything in place.   When it's all assembled correctly, there is expected be about 0.004"-0.006" end play for the camshaft.  See if this different diagram helps.
   

Lorena, Texas (South of Waco)

Ted,

I seem to be missing the thick, non-keyed spacer (6291) in your diagram. I found one from another motor, but it looks just like the beveled spacer that goes behind the gear. Are they the same thickness?

Soffian Adam
Jamestown, NY
59 F100, 55 Club sedan

When I move the slotted spacer behind the fuel pump concentric, only a small part of the woodruff key gets into the concentric. It looks like the timing gear needs to go on a little more. I put the thicker spacer I found, and everything seems right, with the exception of the slight engagement onto the key by the fuel pump concentric.

Although I know I’m supposed to have a lock washer, I have yet to find one on any of the few engines I’ve torn apart. Should I just use a grade 8 lock washer? Or grade 5?

Soffian Adam
Jamestown, NY
59 F100, 55 Club sedan