You should be able to use statsd (open source) or istats menu (commercial).
Note that you will need to replace VirtualSMC.kext, SMCProcessor.kext and SMCSuperIO.kext with FakeSMC.kext, IntelCPUMonitor.kext, IntelMCHMonitor.kext, ITEIT87x.kext and RadeonMonitor.kext as per the guide.
I believe the latest version of FakeSMC.kext should have support for Radeon 9600XT temperature monitoring based on the latest release notes in Github, however to date I have not found a way to monitor the fan speed.
If you search online in some of the usual places, there is a lively debate from the developer of OpenCore where he states that in principle HW monitoring should not be implemented unless natively supported by MacOS to ensure compatibility with future versions of MacOS. Fortunately the developer of FakeSMC takes a different approach.