Hi Uber,
You should be able to mirror ports 1-46 to port 48. After EXOS 15.3, up to four mirror instances are allowed, but this config would only use one mirror instance.
One thing to be aware of, however, is that since you are mirroring 46 ports, there is a potential for up to 92 gbps of traffic to be included in the mirror (1G ingress and egress on each mirrored port). Because of this, some traffic may not be seen on the monitor port due to bandwidth limitations.