Just got them, thanks for pointing me to this. Can I use those as a base to install latest mods?
Yes you can.
You need to install EECH into the same folder as EEAH for it to recognise that you've got them both installed. It just means you get the EEAH campaigns, and the Havoc needles works.
I install mine like this...
\GOGGames\EECH\
Then in there is the Aphavoc and cohokum folders.