1968 power steering unable to center spool adjustment

HI, I have a 68 b body power steering box issue.
Unit was working fine, but was seeping around the spool valve body. I removed valve body and installed new seals.
Reassembled and began adjust to get spool unit centered. It will center but when turned left or right is will continue to drift in that direction. I have done extensive reading on this issue
My spool valve moves freely in housing bore. The spool lever and spring are not damaged and look fine. I don't think there is any issue with the box itself. Has anyone replaced the entire spool unit, to solve this drifting issue?
Sure appreciate any thoughts.

Is this with the wheels on the ground or off ?

Yes with wheels off floor. Also when I start engine, the steering wheel will jerk slightly either left if wheel is turned left and right if wheels are turned off center to right.

Do you have the FSM? The pivot lever has to go in a certain end into the box and has to align into a slot. The spring also has to go in a certain way small end into the box. The pivot lever should pop back to center when pushed either way.

Yes, I'm doing the assembly that correct way. My concern is the the fitting spool valve over the pivot lever as assembling. It almost seems that the lever head isn't fully engaged into the spool valve cavity.
After doing some measurements, the lever height vs cavity it fits in is nearly .100" difference. So,lever is that .100 clearance shorter. I know it should have some clearance.
I was trying to install the pivot lever with spring, into the spool valve, and install together, but haven't had any success as lever head won't stay in spool socket due to the spring pressure. Kinda wonder how
the rebuilding shops do this procedure?

Do you have the end on the pivot lever with the double bearing going into the box? Do you have the pivot levers slot parallel with the worm gear? From the FSM

(57) Install valve pivot lever (double bearing end first) (Fig. 24) into center race and spacer through
hole in steering housing so that slots in valve lever are
parallel to worm shaft in order to engage the anti rotation pin in center race.
Install valve pivot lever spring small end first.
Turn worm until the piston bottoms in both directions and observe the action
of the lever. It must be in the center of the hole and snap back to its center
position when the worm torque is relieved.

The lever will stay down. The spring is on the top. If you do not have the pin in correctly or damaged it taking it apart that could be your problem. What manual are you using??

I didn't take the steering box apart, only removed the valve body from top of box.

I realize that. But you are doing something wrong or have damaged something. Again what manual are you using?

using a 68 shop manual well as a motor's manual.
I did manage to get the spool lever w/spring attached to stay inserted in the spool valve assembly last nite. I installed it and tested. the steering wheel doesn't drift as it did before with the wheels off the ground. Was able to get valve centered.
Seems to be ok now. will test drive today.

Good deal. Back in the day being a tech in the dealership I saw a lot of guys come in with messed up gear boxes. [self inflicted]. That style was Ok but needed a little understanding on how to work on it.

so true.
This is the first time I've had an issue. I've done a few of this type in past and no issues. This steering box doesn't give you a firm feel. It is very easy to steering and sensitive.
I've considered buying a firmer feel for that reason.
Thanx again for your help. Sometimes you have to think out of the box. I wish i knew how the box rebuilders assemble these units.
Tom

To much pump pressure can cause what you are experiencing. As far as I know rebuilders do it just like the FSM says. Experience helps and no doubt has a few tricks. I have a stage 2 firm feel in my car now.