Not sure what you mean by forcing it, but most programmable Motorola radios allow PL or DPL to be programmed and for you to select whether the PL or DPL is in for TX, RX or both. You can also usually have different codes for RX and TX on the same channel.
Never said I wanted to I was just asking if it was possible. Cause I know 006 is a DPL but I wasn't sure if it was a valid Motorola DPL or not. I'm pretty sure the first DPL for Motorola is 023?
I all depends on which radio you're talking about. The Astro Sabers and the XTS5000 that I have right here will not allow "Non-Standard" DPL. The very first one is 023.