Following is what I believe an appropriate invitation to someone to collaborate on a research project. Please let me know if you know someone who can collaborate.
I hope that you are getting on very well. My name is XYZ and I am from ABC. I am a computer scientist by profession. I have a PhD in computer engineering from University of Limerick, Ireland. Currently, I work as an assistant professor at a local Pakistani university.
The reason I am emailing you is that I want to apply for a research funding. The nature of the fund is such that it requires me to collaborate with a principal investigator who is based in the U.S. The research fund is sponsored by the U.S. government and is available to Pakistani researchers through the higher education commission of Pakistan. Here is the link to the call for research proposals.
Among other things, I am particularly fond of working on unmanned aerial vehicles. You can find my research proposal here.