You should be able to change the stacking configuration. This is how it looks on my 6450:
On unit 2 I set the stack ports using
I would expect that something similar is available on the 7250 no matter how the initial configuration was done.
Code:
stack unit 1
module 1 icx6450-24p-poe-port-management-module
module 2 icx6450-sfp-plus-4port-40g-module
priority 255
stack-port 1/2/1 1/2/3
stack unit 2
module 1 icx6450-24p-poe-port-management-module
module 2 icx6450-sfp-plus-4port-40g-module
priority 240
stack-port 2/2/1
stack enable
On unit 2 I set the stack ports using
Code:
SSH@ICX6450-24P Router switch-01(config)#stack unit 1
SSH@ICX6450-24P Router switch-01(config-unit-1)#stack-port 2/2/1