remote locking system; a/c questions

[Lee M. Levitt]

A couple of quick questions...

First, has anyone considered upgrading a '95.5 or '96 style remote system
(post infrared, small flat RF keyfobs) to the later RF system that works
with the fat keyfobs and the switchblade key?

The Bentley describes the infrared system in detail, but doesn't talk much
about the more recent systems. I'm wondering whether the RF controller can
be swapped for a later style controller, or whether more needs to be
changed. I'd expect that all of the components can be salvaged from a donor
car...but I don't want to start taking apart my car(s) to find out that the
two systems are completely incompatible or that I have to change
*everything*.

Second, on *really* hot days, if my S6 has been sitting for a while, once I
start the engine, the a/c will temporariy refuse to engage. I'll press the
a/c button, the light will illuminate, and then go out. This will happen
repeatedly for the first 5 minutes or so, and then it will work as normal.
Is there a sensor somewhere that says "oops, internals too hot for a/c to be
useful" or something similar?

Thanks!

Lee
'95.5 S6 avant
'96 A6 quattro avant