Need to replace oil pump - where is it and how does it come out to be replaced? on 1999 Cadillac Catera

The oil pump needs to be replaced and I am not sure how to take the oil pump out of the 1999 Catera.

Asked by for the 1999 Cadillac Catera
it calls for 10 hours to replace the oil pump...
1. Disconnect the negative battery cable.
2. Recover the A/C system.
3. Drain the coolant.
4. Remove the intake air resonator.
5. Remove the intake plenum.
6. Remove the front timing belt cover.
7. Remove the timing belt.
8. Remove the rear timing belt cover.
9. Remove the A/C compressor.
10. Remove the A/C compressor and power steering pump bracket bolts from the engine block.
11. Position the A/C-PS bracket out of the way of the oil pump housing and secure with mechanic's wire.
12. Remove the generator lower mounting bolt (3).
13. Loosen the upper generator mounting bolt (6).
14. Pivot the generator out of the way and secure with mechanic's wire.
15. Remove the lower oil pan.
16. Remove the upper oil pan.
17. Mount the J 42065 to the crankshaft drive gear.
18. Use the J 42098 to remove the crankshaft drive gear bolt.
19. Remove the crankshaft drive gear.
# Remove the oil pump bolts.
# Discard the old oil pump bolts.
# Remove the oil pump.
# Remove the front main oil seal and collar from the oil pump.
# Clean the oil pump sealing surfaces if the pump is to be reinstalled.
# Clean the engine block (1) and the upper oil pan sealing surfaces.
# Ensure all of the old sealant, gasket material and residual oil is removed
Ensure the guide pins (2) are in place.
1 more answer
This procedure requires a lot more skills, experience and tools that an average DIY guy would have. I'd suggest a repair shop for this problem.
If you are very confident in yourself and have the special tools required, get a good repair manual and don't start the repair unless you read and understand every step of the repair. You can cause a serious damage to the engine if the steps are not followed exactly.