There's two ways... it is technically possible to muck around with VMware Fusion configuration files and adjust the NAT configuration to be in your preset IP range. As you can guess from my wording, I'm not a fan of that (updates might break your manual configuration etc..)
Another way is by using the network editor in VMware Fusion Pro.
This is a feature that is only available in the pro version, but you can create your own networks from the GUI.
Menu VMware Fusion -> Preferences -> Network tab
Click the lock to make changes
Click the "+" to add a new network
Then fill it out depending on what you need.
You talk about having a DNS server, if you also have a DHCP server running then you can uncheck the "Provide addresses via DHCP" choice.
As I said.. this is what I'm using myself, but then with a firewall VM for providing NAT/DNS and DHCP, so I don't have those options checked.
Now you not only have the options for NAT, Host Only and bridged to connect your network adapter to, but also (in my example above) vmnet2 and vmnet3.
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Wil