options for integrated vox/data with VWIC-2MFT-T1

[linguafr]

Current setup is a single T1 p2p with csu/dsu's on each end (routers
and pbx's connected to each) channelizing 4 DSOs for vox the rest
data. Adding a second T1 for additional data bw.

I'm actually helping with this remotely so I have limited access to
csu/dsu's but I'm guessing there's no way to use these external csu/
dsu units with the second T1. That is, bring two connections off the
csu/dsu, one for each MFT port. Alternatively, I see there's a drop
and insert option which sounds like the appropriate application in
which both T1s could connect directly to the router 2MFT card ports,
but am unsure how the pbx would connect. Do I get a an additional
vwic card for the D&I approach allowing for connecting both T1s and
PBX directly to router vwic interfaces. And in this case can I
configure multilink ppp for a fraction of one of the T1s and provide
for the 4 vox channels on a separate vwic card?

Something like this?

#T1 line 1
controller T1 0/0/0
framing esf
linecode b8zs
channel-group 0 timeslots 1-24
!
#T1 line 2
controller T1 0/0/1
framing esf
linecode b8zs
channel-group 0 timeslots 1-20
tdm-group 1 timeslots 21-24

#pbx
controller T1 1/0/0
framing esf
linecode b8zs
tdm-group 1 timeslots 21-24

???