Follow-up
I did some research on the F150online website. Someone mentioned that having an air leak by the air filter caused their P0175 light. I had mine off earlier for the other problem so I reseated my filter and checked all the vacuum hoses I played with. I reset the light and it didn't come back on during the test drive. We'll see what happens after a few more miles.
I also found the below site for troubleshooting the OBDII codes for 2001-2002 gas engines. Has some good tips.
http://www.clubfte.com/users/screwy/0102.html
John