You won't find parts for a 1998 Ford F53 chassis. Ford ran the 1997 model through 1998 and skipped the 1998 designation. In the 1999 model year the 460 was replaced with the 6.8 liter V10.
There is also no 2005 model year F53 chassis. They ran the 2004 model (310 hp V10 with 4R100 transmission) until Jan 1 of 2006. They skipped the 2005 model year designation and went to the 2006 model designation when they introduced the 362 hp (3 valve per cylinder) V10 and 5R110 transmission package on Jan 1 2006.