You can continue to try to figure it out, but allow me to just post the method I referred to in a previous post, the E/O I/C method. Hopefully it'll help.

First, let me explain this: The most important part of the adjustment of lifter preload is making absolutely sure the lifter you're working with is on the base circle ( sometimes referred to as the "heel") of the camshaft lobe. That's what's MOST important! The lifter HAS to be on the base circle/heel.

Since there's no easy way to see into the lifter valley with the intake manifold installed you have to watch the pushrods or rockers. What the pushrod/rocker does tells you if it's companion is on the base circle of the lobe or not. So you watch one to adjust it's companion.

That being said, here's the way I find to be the easiest and less prone to error or confusion:

Start with the #1 cylinder (you can actually start with any of them, but starting with #1 eliminates unnecessary confusion).

Turn the engine over and watch the #1 INTAKE pushrod. As you turn over the engine (either with socket/ratchet on the damper bolt or with the starter)that pushrod (the INTAKE) will, at some point, begin to rise.

Continue turning/bumping the engine over until that INTAKE pushrod completely rises (indicating the valve is competely open) then begins to lower (indicating the INTAKE valve is closing).

Just before that pushrod has completely dropped to it's lowest position STOP turning. The point that you actually stop turning over the engine isn't that critical, so anywhere between half-way before it has completely dropped and just before it reaches its lowest point is fine. Shoot for half-way.

At that point you'll KNOW the #1 EXHAUST lifter is on the base circle of its lobe.

Now you set the #1 EXHAUST. Yep, the EXHAUST. You watch the INTAKE to set the EXHAUST; sounds strange but that's exactly how it works. Hence I/C of the technique name.

You then move to the #1 EXHAUST, back off on its adjusting nut/poly lock until the rocker is loose and you are able raise and lower the pushrod with your fingers.

Now, gradually begin tightening the nut/poly lock until the pushrod can no longer be raised or lowered. Just at the point that all the slack/up and down movement of the pushrod has been removed YOU'VE FOUND ZERO PRELOAD.

Now is the time to set the preload. Some like 1/16 turn, others 1/4 turn, still others like 1/2 turn (which is what CompCams and others recommend). GM recommends ONE FULL TURN from zero on many of their stock engines and TPIS is now advocating a minimum of 2 FULL TURNS! Your choice.

I go with CompCams' recommendation since they say you should achieve about .030 of preload. Since measuring .030 is a bit difficult with the intake installed, 1/2 turn is a VERY GOOD approximation.

Once you set the preload on the #1 EXHAUST to where you want it, lock the hex head screw by turing it in a clockwise direction until it's tight. I even put my socket on the poly-lock and give the lock another little tightening turn just to make sure it's tight.

Now it's time to deal with the INTAKE.

Continue turning the engine, but this time watch the EXHAUST pushrod or even the rocker arm. Since you just finished setting the EXHAUST, watching the EXHAUST rocker can be relied on to be accurate.

Turn/bump the engine and AS SOON as the EXHAUST pushrod begins to move UPWARD (indicating the EXHAUST valve is beginning to open) STOP turning/bumping the engine.

You can now set the preload on the INTAKE, in the same manner as you just did. Back off on the INTAKE rocker nut/poly lock until the INTAKE pushrod can be moved up and down. Then begin gradually tightening the nut/poly lock until all slack has JUST been eliminated and the pushrod can't be raised or lowered. THAT'S ZERO PRELOAD/LASH. Now set the lifter preload the number of turns you decided to use.

Now move to the #3 cylinder (which is the next one in line on the driver's side). Once you've done #3 move on to #5, then #7. Now cross over to the other side of the engine and begin with #2, the #4 and so on down the line.

Here's the reasoning behind the E/O I/C technique:

When the EXHAUST rocker just begins to move, the INTAKE lifter is on the base circle/heel of its lobe. When the INTAKE pushrod is anywhere between being half-way down and all the way down, the EXHAUST lifter is on the base circle/heel of its lobe.

That's why it's called E/O I/C INTAKE CLOSING - EXHAUST OPENING. After you've done one or two cylinders you'll come to realize how truly simple this method really is. I just finished building a 388 LT1 for my 96 Vette and guess which lifter preload technique I used. LOL

I really hope this helps because I know how frustrating this can be.

Jake