86 Evinrude 25 Problem Shifting

Hi all,
I removed and disassembled the lower unit to replace the seal set and to inspect parts for wear, also replacing the water pump's impeller, key & water tube grommet.
I reinstalled the lower unit today and it seems now I'm having difficulty with the shifting.
It's currently in forward gear and can't shift to neutral or reverse.
Does anyone who's done this work before know what the problem(s)
might be? I'm sure that the shift lever, yoke, and cradle are correctly in place
along with the phillips screw that retains the shift lever in place. Any ideas?
The model of my Evinrude is an E25ECDR.

Did you assemble the shift rod connection behind the water intake screen properly..... including the very small funnel shaped plastic retaining ring? Without that item, the shift rod simply slides up and down at that point without moving the lower unit mechanism.

Good point, Joe. Yes, both the upper and lower keepers are in place. What else might be causing the
problem? I haven't tried starting the engine yet- am working on a fuel leak. The drive shaft is meshing,
as I can rotate the flywheel and the prop shaft turns accordingly.

Two keepers? Only one I'm aware of is that plastic insert. However..... With the water intake screen removed, if you can verify that the short threaded shift rod in the lower unit is actually moving the same distance as the adjoining upper shift rod, I can only assume something is amiss within the lower unit.

What I meant about two keepers (black plastic funnel shaped inserts) is there is one on the upper
shift rod and also one on the short lower shift rod. I sure don't look forward to having to disassemble
the gearbox again, but will plan to do it if it's necessary to correct the problem.
Thanks for your input on this Joe! I'll post back when and if I figure it out.