yep this is what I used to set remote address, and created a firewall rule what that address may access on the network, but the user can go to VPN interface set up on PC and manually change IP address within IPv4 settings and I believe it will work and this way user goes around the firewall rule.I think user-man with an attribute of framed-ip-address=x.x.x.x for that user.
If the number of users is not large and you don't want to set up any Radius, you could also use remote-address=x.x.x.x.