Running rough and codes P1763, P300, P302, P304 and P305

Originally I had an O2 sensor code. I replaced the upper stream O2. The next day I got a different code for the transmission governor pressure sensor. I went to change that out by removing the transmission oil pan. I then realized I had the wrong part. I put transmission oil pan back on and refilled with fluid. I drove about 30 miles the next day. Vehicle was running as usual. The following day the vehicle was running very rough. The correct transmission sensor finally arrived and I changed it out. That changed nothing. I got the vehicle up to the auto store for the code reader. It now reads the same P1763 regarding the transmission sensor with P300, P302, P304 and P305. The code reader print out says it's most likely the crankshaft position sensor. The problem with that is I can't find the thing. Should I take it to the mechanic? I am not sure what to do anymore.