gigcass, your 1st idea works nicely. With your pointer, that the digit map is what needed changing, I used the OBITALK tool to provision GooglVoice, to see how 1541 was incorporated into the digit map. It is now incorporated into both accounts here, SP1 and 2.
GoogelVoice: (*xx|1xxxxxxxxxx|<1541>[2-9]xxxxxx|<1>[2-9]xxxxxxxxx|011xx.|xx.|(Mipd)|[^*]@@.)
Nice to awake and find the question answered here. I've learned a bit more. Thank you.