CyanogenMod 7 RC3 was out but not yet for HTC HD2. So do be patient and try out TyphooN CyanogenMod 7 RC2 first. Basically, it is based on CyanogenMod 7 RC2 for HTC Desire which has Android 2.3.3 Gingerbread and using Tytung r8.3 Kernel.
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Download TyphooN CyanogenMod 7 RC2 v2.8.4 [Kernel: Tytung r8.3] NAND A2SD+ Zip ROM here.