Hello, I have a few issues with my Civic with 133,000 miles that are somewhat puzzling.

1. Creaky rear suspension just developed. Lubed all bushings but still creaks when pushing on left side (loudest creak). I'm thinking it can now only be the strut. Ride is still good though. If it is the strut, how hard is it to replace for a reasonably mechanically inclined person and what slightly firmer strut could I replace it with for a more controlled rear. I don't need a rock hard ride just something a bit better than stock.

2. Engine resonance/buzzing at 1400, 2800 rpm. A minor annoyance that I've had for 50,000 miles. Sounds like a loose heat shield, but nothing appears loose and problem has not worsened since. Any ideas?

3. Driver's side power lock activator dead. Looks tricky to replace since it seems to be part of the locking mechanism at the rear of the door frame (part that meets the "B" pillar when closed).

Thanks for any advice