I find the spring to be much easier to install with the adjustment backed off, so I usually put it on first and then do the adjustment. One method is to have the linkage connected, unscrew the adjustment until it is solid (meaning the pushrod is holding the bearing against the fingers), turn the nut until you have the specified gap between it and the clevis; then turn the pushrod until the nut touches the clevis. Tighten the nut and you're done. Written up in the TR4 workshop manual, I think.
I just pull the lever against the spring as hard as I can, and check that there is some free play in the pushrod. I prefer mine tighter than the factory adjustment anyway, and don't mind checking it more often. The adjustment closes up as the clutch wears, and it's important that there always be some clearance.