Hi All
Great Forum, found out lots of usefull stuff
Is there anyway to mod a Stringz n Thingz kbd to control a 4700 modular

In theory, yes.

The Stringz'n'Thingz has two contacts per key, one used to key the notes, the other to activate the noise gate. The latter could be replaced by adding diodes to the keying contacts, and deriving a gating signal from that, thus freeing up one set of contacts. Those contacts could then be wired with a resistor network to replicate the control-voltage generation of the 4700 keyboard (I assume you're referring to the analog keyboard, not the 8700-interfaced digital one). You could then use the aforementioned noise gate signal to create a trigger and gate for the 4700.

There would be more details to work out, but off the top of my head, it looks very doable (but a fair bit of work).

Also, it is simple interfacing the 1550 Stringz-n-Thingz to a PAiA 2720 and 4700 series modulars as is described and illustrated in the pdf linked below (from the second paragraph and on). These pages from the 1550 kit manual detail using the audio and gate-trigger as inputs to synthesizer modules.

1550 Stringz-n-Thingz Audio Post Processing