Accessing modem on different sites - same IP

[dan2112]

I have two homes connected over a site to site IPSec tunnel.
I would like to login to my modems from either location. The problem is they have the same IP address (192.168.100.1).

I was thinking about setting up a NAT on either side that says 192.168.100.1:8080 be routed to the other site and Port Translated to 192.168.100.1:80 and visa versa so the other homes modem is always on port 8080 regardless of which home I am in.

Could somebody offer assistance on how to set that up - I am not sure if I need just a plain route saying send all :8080 traffic to the tunnel or I need additional IPSec config.

Figured I would ask here first.

Dan