box1
/etc/zaptel.conf:
loadzone = us
defaultzone=us

dynamic=eth,eth1/00:30:48:84:74:25/1,24,0
bchan=1-23
dchan=24
dynamic=eth,eth1/00:30:48:84:74:25/2,24,0
bchan=25-47
dchan=48   
dynamic=eth,eth1/00:30:48:84:74:25/3,24,0
bchan=49-71
dchan=72    
dynamic=eth,eth1/00:30:48:84:74:25/4,24,0
bchan=73-95
dchan=96

/etc/asterisk/zapata.conf
[channels]
signalling=pri_net
switchtype=5ess
callerid=asreceived
group=1             
context=default
channel => 1-23,25-47,49-71,73-95

box2 
/etc/zaptel.conf
loadzone = us
defaultzone=us

dynamic=eth,eth1/00:30:48:76:27:5D/1,24,1
bchan=1-23
dchan=24
dynamic=eth,eth1/00:30:48:76:27:5D/2,24,0
bchan=25-47
dchan=48   
dynamic=eth,eth1/00:30:48:76:27:5D/3,24,0
bchan=49-71
dchan=72    
dynamic=eth,eth1/00:30:48:76:27:5D/4,24,0
bchan=73-95
dchan=96

/etc/asterisk/zapata.conf
[channels]
signalling=pri_cpe
switchtype=5ess
callerid=asreceived
group=1             
context=default
channel => 1-23,25-47,49-71,73-95