This may be a tough question, but does anyone know the diameter and length of the rod inside the FPR? I've got access to a lathe and was going to machine a solid stainless rod with the extra length instead of using one of the different materials for a shim.

 

i dont know the length, but i know the amount to shim the FPR tends to vary from truck to truck. you could take the stock one out, measure it, then make a plunger that is .055,.065, and .075 longer and try them each to get the desired fuel pressure.
most of the time a .065 shim will get you around 63-68psi

 

I was figuring that I would have to take it out and measure it. I was just taking a shot that someone might have the dimensions. Just curious is this along the same lines as the 10k mod?