Does anyone know if its possible to cut the wires and get access to above
mentions 4 connections ? Or use the plug in any way ??

Visit the raymarine.com website and ask.

If it's the E45003 speaker then it attaches via a handset connector on the
radio. The connectors have 8 pins. It's reasonable to assume there's lines
for data in/out, power, ground, speaker +/- and mic +/-. The handsets
support showing data, which the speaker would ignore, of course. It may not
be just plain NMEA. The VHF radio manual mentions the connector being
detailed in the installation guide, but I haven't seen that on their
website.

I have, however, had past success asking Raymarine support for technical
info and getting useful answers. You should try that. Summarize here to
help others find the answer in the future.

-Bill Kearney