Finally, MIUI Android 4.0.3 Ice Cream Sandwich ROM is available on Amazon Kindle Fire. However, it is an alpha version. So do expect bugs flying around here and there. And force close issue is a norm too.
Antutu Benchmark failed to complete (hang there). So I don’t have benchmark score for this MIUI Android 4.0.3 ICS alpha ROM. But it does look promising. Looking forward for stable version soon.
Installation guide ~ How to install custom Android ROM on Kindle Fire with TWRP 2.0? (Video)
Download MIUI Android 4.0.3 Ice Cream Sandwich ROM v2.2.3 alpha for Kindle Fire here.