SonicWALL Transparent Mode Equivalent on Fortigate

[geant90]

We are moving a client from a SonicWALL to a Fortigate. Currently ISP is providing two IPs

Public IP 90.90.90.140 Server Public IP 90.90.90.150

WAN Port set with public IP and the server is set with the .150 IP only allows HTTPS to reach the server.

What would be the equivalent of SonicWALL's Transparent mode and how would I go about setting it up.

So far I have the Fortigate configured with the WAN IP but where I am confused is setting the DMZ with the server using the .150 I know I have to use a VIP for the .150 But how do I do so allowing the Server to keep the external ip 90.90.90.150 on a DMZ that only allows https to the server. How would I configure the port for the server on the Fortigate? Any help is appreciated.

Respectfully,