which is the easyst way to change working MT IP and gateway so,
that after it still alive. ( MT is 40-45 km. away ).?
MAC telnet
mac telnet is good, but this MT is not in my subnet.
the only way i think is over MT ethernet with winbox or make MT backup and then change it another MT and copy backup back and reboot MT. ( this is high risk if MT is not boot up or IP’s is not correct then i have to drive 40-50 km 
or someone help me write little script which do all work.
( change IP and gateway ) ?
this should be easy: login to this “far away” server from some server or computer which is on the SAME subnet on ethernet as this faraway server - ie. if this is 192.168.0.1, login to it from 192.168.0.2 etc, ADD new IP adress to it, and do:
/ip route
print
set -number-of-default-gateway new-gateway-ip ie. set 14 10.10.0.1