As far as I know, there are at least 5-6 Nepali ACCA students and affiliates/members in US doing their CPA. All of them were gone through the 150 credit hour process. You don't want to be restricted to work in other states just because your licence is  from Colorado or Vermont. On top of that, it is way harder to pass the CPA exam from your ACCA knowledge. To test your knowledge, you can register in an accounting class in any community college, I bet you will get an unexpected result. So, I'd suggest you to take some accounting classes to fulfill the 150 requirements first, rather than jumping in to sit for the CPA exam with 120 and ACCA. 

My two cents!! 

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