I tackled the job today, and here's the procedure I used for my '98 1.6 liter:
1) Disconnect negative cable at battery.
2) Remove throttle cover (plastic cover, held in place by 3 bolts)
3) Disconnect the accelerater and A/T throttle cables- the cable ends unhook easily. You'll have to loosen the locknuts holding the cables onto a bracket.
4) Remove the air intake pipe. This is somewhat involved. You'll need to:
- Loosen the hose clamp on the throttle body end of
the pipe
- Disconnect 4 hoses from the air pipe. The two that
attach to the u-shaped metal pipe near the middle
of the air pipe carry coolant- so be prepared for them
to spill a bit.
- Remove the two bolts holding the air pipe onto a
bracket (at the bend in the air pipe).
- Pull the air pipe off of the throttle body
- Where the air pipe connects to the air filter box,
unscrew the two bolts holding it down to the filter
box. Detach the electrical connector
- Pull the air pipe out of the air cleaner box.
- Remove the air pipe bracket
5) Pull the PCV valve from the valve cover
6) Remove the spark plug wires
7) Remove the six bolts holding down the valve cover

(Finally!) Pull off the valve cover
Whew! Suzuki didn't make it easy to get to those valves!