It is possible to whitelist datafields in a pushreport. It is possible in both the CMe2100 and the CMe3100. 
The only difference between them is the procedure in how it is made. The CMe2100 will be administrated by sms commands or console (TELNET), while the CMe3100 will have the same commands sent via the console (TELNET).

The CMe3100 console is described here

The reason to do this is to minimize the report, both in data size and how it appears visually.

This function is called Filterlookuprecord.
It is applied on pushreports individually, so if you activate it on report1, it will not affect report 2,3,4,5. It will affect report1 untill the function is disabled again.

possible ways to activate it:

set report1.filter.lookuprecord.enabled=true/false
set report2.filter.lookuprecord.enabled=true/false
set report3.filter.lookuprecord.enabled=true/false
set report4.filter.lookuprecord.enabled=true/false
set report5.filter.lookuprecord.enabled=true/false

set report1.filter.lookuprecord.includelist=
set report2.filter.lookuprecord.includelist=
set report3.filter.lookuprecord.includelist=
set report4.filter.lookuprecord.includelist=
set report5.filter.lookuprecord.includelist=

Now all you need to do is to tell the function what to include. It must be specified like these examples;

"mbus.dib.energy no-error.0.0.0.0"
mbus.dib.ext-temp.0.0.0.0
mbus.dib.energy.0.0.0.0
mbus.dib.volume.0.0.0.0
mbus.dib.flow-temp.0.0.0.0
mbus.dib.return-temp.0.0.0.0
mbus.dib.diff-temp.0.0.0.0
mbus.dib.power.0.0.0.0
mbus.dib.rf-level.0.0.0.0

etc

So if you want one of these to be whitelisted in report1, send

set report1.filter.lookuprecord.enabled=true
set report1.filter.lookuprecord.includelist=mbus.dib.volume.0.0.0.0

If you want additional fields to be included, just continue with a ","
example;

set report1.filter.lookuprecord.includelist=mbus.dib.volume.0.0.0.0,mbus.dib.energy.0.0.3.0,"mbus.dib.energy no-error.0.0.0.0",mbus.dib.energy.0.0.0.0

Note that you never can remove the header information (such as serialnumber etc) from the report. So If you want a slimmer report, use another template like the x108 which contains less information.