You don't install the kernel in AmonRa. You need to fastboot flash the kernel. If you extract the boot.img file then do this:
From a command prompt(assuming you have the Android SDK and necessary drivers)
'fastboot flash boot boot.img'
If you have a PH98IMG.zip that came with the ROM, drop it on the root of your SD card and reboot into the bootloader(power down, then power up holding power and volume down). The phone should immediately start to flash the kernel.