Oberheim Echoplex question

[James Richmond <richmondjames@me.com>]

Hi people,

I am back after a long absence (around 3 years).

I am working with the Gibson Echoplex these days and wondering if I  
can do something.
I have a footpedal with it but i sometimes want to use a guitar  
mounted switch (momentary) to control the 'insert' switch.
I want to be able to do extremely fast granular synth style noises and  
a finger is more responsive than a foot.

I am wondering if I could build a switch with a 4.75 kOhm resistor in  
series and have that connected to the echoplex at the same time as the  
foot pedal (with a custom Y cable).
Is this going to work?

Lastly,

Do I have any chance of finding ram expansion for an original Lexicon  
Jamman?

Regards,

Jim Richmond