Insert new units

[Max]

Hi to all!
Help to me. After some years I'm restart to play with OFP (now with ECP and DMA Army pack).
I should like to change the good DMA's western troops with Faceplant Modern US army v 1.30 ones....I've tried to change the config, but isn't my work, I'm really a newbie for this. After hundreds reading of the config I realize I don't know where I must insert every text change.
There is anyone who might help me or is there yet a config with that issue?
Thanks a lot!