You are going to very happy with the improvement in handling with any one of the headsteadies (sp?). I've had the Norvil, Dave Taylor, and a Jim Comstock's heasteady. They are probably equally effective in getting the job done but each one of them has issues.
The Norvil is a PITA to get set up. The crucial factor is that the side plates need to be square with the endcaps so that when you check the clearance, like servicing the other iso's, it's uniform all the way around. The plate is attached to the frame at the welded in lug and the clamped on bracket. It is attached to the iso by the though-bolt. For the plate to be square then, the length of the lug, the clamped on bracket, and the combined length of the steel part of the two bushes in the iso have to be
exactly the same. And they have to be oriented so the are
centered in the frame to within a couple thou. Mine didn't come that way so it took some filing and shims, make that a lot of filing and shimming.
The Dave Taylor heasteady uses 5/16" rod ends. They wore out after around 7,000mi. They should be sealed and packed with grease. They would probably last longer if they were 3/8" too.
http://www.aircraftspruce.com/catalog/a ... ckkey=4183
Jim's headsteady is a more developed piece in every way. There is one thing to pay attention to. The mounting bolts have a taper that fits into a taper in the aluminum bracket. If you over tighten the nut it will pull the bolt through the taper in the bracket. Jim Fixed it with a threaded steel insert, for free.
edit: It was obvious that I screwed it up, he didn't bring it up. Most people can't pass up low hanging fruit like that.
Dances with Shrapnel said:
If it were me, I would make my own, either heim joint or teflon puck/slider ala Herb Becker. See Doug McRae's post on the subject. Eloquent, simple and robust.
Ludwig made a nice headsteady using the pucks. I ran across some posts but they all had expired photobucket pics. You might be able to find something. Ludwig hasn't been active on the list for a while.
There are quite a few nice DIY heim headsteady threads. You might want to think about using a larger rod end and seals.