I have to stand somewhat corrected.
create a filter "internet.out"
Contents:
three lines for each net block you have:permit 1.2.3.4/20 tcp
permit 1.2.3.4/20 udp
permit 1.2.3.4/20 icmp
The more appropriate format would be:
permit 1.2.3.4/20 0.0.0.0/0 tcp
permit 1.2.3.4/20 0.0.0.0/0 udp
permit 1.2.3.4/20 0.0.0.0/0 icmp
You are *supposed* to use a src/dest netblock pair, though I have
set up and used w/o a dest address and it worked.
final line to log (optional) MUST COME AFTER permit list for netblocks:
deny log
If you choose not to log, then you need a line:
deny
Otherwise that which falls through isn't denied, obviously.
Doing router filters while fatigued is often a problematic process.
Try and work on them when you aren't so tired, unlike me when I
sent my first mail 
-george william herbert
gherbert@crl.com