NOT necessarily suggesting you have to do something different, but have you read anything about the Grassroots4x4 center link upgrade?
Here's my process. The one additional thing that could be done would be making an adjuster to fit 1-ton GM tie rod ends. Would require a 7-degree taper reamer to ream out center link and spindle.
The OEM idler/pitman should be kept, because the aftermarket ones all suck (I've tried proforged, MOOG, etc), and bent them all. None of them are built nearly as well as the OEM ones.
Anyways, this would be something you could put together as a bolt-on kit (minus the GM tie rods if you go th
Steering Upgrades
This post includes installation of the following:
Background: The steering on the 1st gen Frontier and Xterra is a notorious weak point of the vehicle. The problem is that the
drag link has a ball joint in it where it attaches to the
pitman arm. This make the steering really smooth, but it allows the drag link to twist when it takes a side-load impact from the tires via the
tie-rods. The tie rods force the drag link up and it rotates on the ball joint. The problem comes in on the other side. The drag link attaches to the
idler arm via a ball STUD, so it doesn't twist relative to the idler arm that it is attached to. All the twisting force is thus translated through the drag link, directly into the steering idler arm, which bends it upwards. The tie rods then collided with the frame when steering back and forth since the idler arm has been bent upwards. This probably don't happen much on smooth roads unless you hit a curb, but while wheeling, side-loads on the tires happen quite often. Here are some pictures of the problem:
Bent idler arm; again, note damage to frame above arm from tie rod end collision during steering.
SO, not a great design overall. It's weak, and the aftermarket idler arms only make the problem worse. If you do ever need a new idler arm, I would stick to OEM only. They are much thicker and prohibit bending. My original OEM took me 2 years of wheeling to wear out, and it was the original one. I've done 4 aftermarket ones this last year alone.
For quality/size comparison, see OEM on left, bent aftermarket on right.
Grassroots4x4 drag link:
So I got a new drag link. It looks like Bryan over at grassroots4x4 cuts the ball joint and ball stud off and replaces them with some sort of off-the-shelf bearing. Due to this, however, it requires that the user drill out the pitman arm and idler arm to a 5/8" straight hole instead of the tapered hole that accepts the factory drag link.
Modified steering arms:
I decided to machine out the idler and drag link to 3/4" and use a bronze 3/4"O.D., 5/8" I.D. bushing to reduce the hole. This is probably completely unnecessary, but I did it thinking that, on the off chance the hole in either of the arms wallows out over time, I can just replace the bronze bearing then instead of having to modify an additional steering arm.
Machined the factory pitman and idler arms this way. Made the hole 0.753" diameter to accept the 0.750" O.D. bushing.