[Collins] Collins mods?

[kiyoinc at attglobal.net]

I was tuning around 40 meter CW last night and got to thinking
about S-lines and Collins mods.

I vaguely recall an S-Line or KWM-2 with a push-button spotting
control.  It was built into the bandswitch knob which seems to
be a hard place to add a switch.   

The motion was to press the button with a finger and turn the
knob with a thumb left handed while writing or using the bug
with the right.

Was this a mod or RPQ or an add-on kit from Waters?  Or did I
misremember it from 40 years ago.

I also saw a KWM-2A with horizontal switches below the PTO
knob.  These were 312B-4 style lever switches and I believe was
a one-off modification to integrate some 312B-4 functionality
into the KWM-2A.  Not factory but it sure looked factory. Or
was it?  

About 1975, I saw an R-390A with a factory installed red LED
digital counter.  This was at a Gaithersburg hamfest. The
vendor had a manual for it.  I don't know whether it was a
frequency counter or a display that sensed the gear settings. 

The fit and finish of the above mods was excellent.  These were
not hack jobs. 

de ah6gi/4