The buzzing is probably the magnetic relay inside the actuator
attempting to move the latch. Have you tried testing the actuator you
have with the latch disconnected? Relays tend to work all or nothing,
so if you have the actuator working test the latch. If it sticks
and/or needs lubrication, try some WD40. Sometimes the keyhole lets
moisture in and causes the latch's ease of operation (when it was new)
to deteriorate. If nothing else . . . you learn weather you need only
the actuator or the whole dang thing.
On the hard to reach bolts problem. I use a flex cable. Its a 10 inch
flexable adapter that takes nut drivers and 1/4 inch sockets.
Good Luck.

techman41973@yahoo.com wrote:
> I have a 97 accord coupe with about 160K. When locking my power locks,
> the door lock actuator in the passenger side door makes a loud buzzing
> sound.
> I took apart the door panel and looked at the necessary steps in
> service manual.
> I have the option to buy a replacement actuator or a new latch with an
> actuator already attached.
>
> 72115-SV2-003 ACTUATOR ASSY., R. DOOR LOCK $88.45
> 72110-SV2-013 LOCK ASSY., R. FR. POWER DOOR $136.53
>
> I would prefer to buy just the actuator and attach it to the old latch.
> (would save me about $50). Can anyone attest to the difficulty in doing
> this? Or is it best to replace the entire module (latch + actuator
> completely assembled).
>
> Also when removing the outdoor door handle (necessary to replace the
> actuator), there are two bolts (accessed from inside the door) any tips
> in how on how to remove the hard-to-reach bolt?