A May 1 AD (2003-09-09) extends the provisions of an earlier airworthiness directive calling for a one-time inspection to check for chafed or damaged wiring in the fuel boost pumps in about 370 U.S.-registered Cessna 441 Conquests. The new directive makes the one-time inspection of the earlier AD a repetitive one (at 200-hour intervals) and requires the eventual installation of an improved fuel pump and wire-harness design. Replacement components are expected to cost about $13,500 per airplane. There have been no accidents reported as a consequence of the problem. The AD becomes effective June 24.