Autopsy complete. Results
!.623 is .020 short of 1.643. Not that it should matter that much, if anything, the seat and open pressures are a tad higher. Not a big deal. But, in terms of preload. There are always to adjust it. The best way to determine what you need is bolt it all together, sans the intake. The cam should be degreed, and the lifter rotation verified by this point. (so that particular lifter is staying in that particular bore) Then use a wire feeler gage to check how far down the plunger of each lifter has been pushed by the torquing down of the fulcrum. The distance between the plunger and the retaining clip is what you need to get. For each lifter, when the lifter is on the base circle. (lifter not on any part of the lobe, only the flat of the journal) If you have more than .010, but less than .030, you should be fine. You may fine you have .040 or more. Too much preload can lead to probelms, and wiped lobes. You may also find that some may have .025, and some have .055 (I'm assuming the plunger can travel that much). If that were me, I'd adjust that to even things out better. In terms of adjustments, if there is too much, you can get shorter pushrods, or get adjustable roller rockers. If there is not enough, you can go longer pushrods. There should be enough room in the lifter motion to get a shelf available push rod to solve any problem. But, you may need to buy them seperately, instead of a full set. Adjustable rockers may solve the preload issue, but may not give the best rocker geometry.