Do know anyone else who put the Borgeson steering box in an 03 or 04. What did they have to say. Sounds like you may have put one in.
There is no difference between an 03 and 05, same stock steering setup. Yes, I wore out the stock box on my 05 and replaced it with a Borgeson box from Geno's.
I started with sloppy steering. The box was wore so bad that when I took the slack out of the pitman shaft it was sticking crossing center. Bad ju-ju. Replaced the box with the Borgeson and updated the sway bar links with MAXX links and poly track bar bushings. Much better, fresh alignment and it was easy to steer at road speeds with one finger on decent roads.
When you got into rough roads and highly crowned surfaces steering was unpredictable at any speed. Lots of random wandering. Ball joints had way too much play. Replaced them and shocks with Bilstein 5200's, another large impovement.
Steering was still unpredictable in uneven surfaces and rough roads. Upgraded the steering to the newer t-type style as tie rod ends had slack, not huge amount but they were worn. Added steering brace at the same time. Another improvement, the biggest difference is the steering is exact now with good road feel. You can feel the suspension working on uneven surfaces and when you turn the wheel to steer there is no over\under steer like before.
I am running 5 degrees of caster with almost worn out MT tires. Also, lower control arm bushings are worn and driver side is creeping on caster adjustment. A set of lower control arms and new tires should effectively make it almost race car tight again. should be able to back it out to 4 degrees caster to save bearings and even out steering response a bit. I am even running without steering damper at this time and it still rock solid. Need to get the dual stabilizer kit for the updated steering bar as it is so much larger.
FYI, Borgeson has the new pitman arm for the 08+ steering setup also. They don't have it on the site or listed yet but have it available.
Steering feel and performance is not just box. Every single piece plus laignment has made a difference.