MCO (Orlando) used to be McCoy Air Force Base (formerly Pinecastle AFB, after the nearby little town). It was named after USAF Col. Michael McCoy.
RSW (Ft. Myers) was named after the airport, Greater Southwest Regional. Since there was already a code for SWR, the R was placed in front of SW.
------------------
AlphaSigOU
Causa latet vis est notissima - the cause is hidden, the results are well-known.