Ok have a few questions about installing a comp cam in my 02 silverado 5.3l- Cam is the Comp XR265HR- Motor has 82K miles.

1. Will I need a new timing set from Comp so I can degree the cam?
2. Is it even necassary to degree the cam? Will stock timing gears/chain work?
3. Will comp 918's work with stock retainers? If not is there any significant difference between Comps steel retainers vs there titanium besides weight?
4. Oil pump- Should I replace? Still has 45psi at idle warm and over 60psi while driving.
5. Lifters? Stock ones ok or should I go LS7?
6. Other than pushrods anything else I should address while Im in there?
Any thoughts will be greatly appreciatted, Thanks-