How to get a job at Microsoft as a Project/Program Manager

I have a well-rounded and somewhat unorthodox background. Master's degree in Biomedical Engineering, worked in Automotive, then Systems Engineer in Aerospace and Defense. I am a Project/Program Manager at a large aerospace firm managing $20M+ in accounts combined. 12 years experience in total. I applied to several remote Project Manager type reqs and was referred by a Microsoft employee. Understanding how difficult it is to get a job at Microsoft, what are my chances? Am I in the IC4-IC6 (64-66) grade level? Do you mind sharing any tips and how was your hiring experience?