So, I'm pretty sure I've suffered a fairly large setback with my rear axle. It seems as the longest 30 spline axle shaft I can get my hands on is 39.625" and i need a 40.625" shaft. I think i may be able to get a 35 spline shaft in that length, but the 35 spline side gears for the ARB RD166 will not fit in my RD21. I've got one more source to check with for axle shafts, but it will be of the double spline variety and be almost double the cost of what I budgeted for shafts.
So, I've started to search for a complete D60FF around here on the cheap, but there aren't many to be had on CL.