Yes, we did this 10 years ago when we first got the 11C with PRI trunks.
Before you do this, and if you have newer code levels, you might look at the new ESA features to protect against 911 misdials.
If you still want to do this, it is done by changing AC1 in LD 86, under the FEAT ESN. PRT the existing ESN before you change it.
You will want to confirm that there are no numbering conflicts in the 8* range.