Cisco IOS NAT Port Forwarding

Testing static NAT and saw some behavior that confused me. In my setup, R5 is the router in the middle doing NAT. I am trying to telnet from R4 which is directly connected to R5 on 155.1.45.0/24 network to another router R8 which is also directly connected to R5 on the subnet 155.1.58.0/24.
In one configuration where I put R4 on the outside interface, telnet works but when I swapped the configuration so that R4 is on the inside interface, it didn’t work. R4 is going to do “telnet 155.1.45.44 8023” in both scenarios. The only place I am changing the configuration is R5.

Working configuration:

interface GigabitEthernet 0/0 (connected to R4)
 ip nat outside
! 
interface GigabitEthernet 0/1 (connected to R8)
 ip nat inside
! 
ip nat inside source static tcp 155.1.8.8 23 155.1.45.44 8023

Not working configuration:

interface GigabitEthernet 0/0
 ip nat inside
! 
interface GigabitEthernet 0/1
 ip nat outside
! 
ip nat inside source static tcp 155.1.45.44 8023 155.1.8.8 23 

Any ideas regarding this? I am able to telnet in one setup but the other I am not.

Edit: Never mind, the other direction the translate would not be on source but destination instead.

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