One minor change i think was made in
1996 with the first year of OBD-11 was that the dish in the 5.9 piston crown was enlarged from about 11cc to about 14cc, and the piston to head clearance may have been increased a bit too, so the compression height or block deck height maching may have changed too.

The piston to block clearance of some of the 1994s seem to be in the range
0.50 to 0.59
while the after 1996 ones seem to be
0.70 to 0.80 inches

The 1995 Field Service Manual specification table
lists the static compression ratio for that year Magnum 5.9V8 as 9.1

In 1996 and beyond Chrysler advertised the Magnum 5.9 v8 as static compression ratio 8.9

OBD-1 had egr to help control NOx
Then this was dropped with OBD-11 in 1996
and it makes a little sense that they might have had to
drop compression a bit
with a changed cam and
a different catalytic converter as part of the emissions control.

Willem Weertman says in his book
"Chrysler Engines"
that the 1994-1995 iron block Truck V10
used the same eutectoid alloy cast aluminum pistons as the
1993-1995 Magnum V8 as a cost saving measure.

I have a set of 1994 pistons from a Magnum 5.9 that i measured
a compression height of 1.61 inches,
11 cc piston crown dish and
472 grams bare piston weight without rings or pin.