Double outbound route question

Hi all,
my problem is the following:
on the same asterisk box I have 2 different PRI channels groups.
dialing from a phone a number with leading zero, I have to dial this number (stripped out or not by the leadnin zero) on one zap trunk or the other zap trunk. I would like to accomplish this using custom context.

In other words, people from one “organization” should dial out using ZAP g1, and people from another organization should use ZAP g2.

Both of them shoul use zero-starting numbers.

I was trying to use custom context module, and disabling or enabling the use of a dial out route: Could this approach work ?

thanks in advance,

Andrea