I have a Bently, but am a little unclear on the proper procedure for
setting the timing on my 85 Westy (automatic), would appreciate
advice:

As I understand it, first I bypass the idle stablizer, then set the
timing (to 5 atdc as per bently, or 5btdc as per list wisdom), then
set the idle to about 850 using the idle adjuster screw.

Question: for this first step, should the engine be cold or hot?

Then I reconnect the idle stabilizer.  Here is where I get confused:

With my old stabilizer, the timing would jump 10 degrees advanced and
the idle would speed up (I'm assuming that it's broken and I've
bought a new one to try).

So with the new (hopefully working) idle stabilizer, do I then:
   reset the timing?
or
   set the idle speed with the screw?
or
   both
or
  neither : it should just work.

Thanks!