Re: 2000 Ford Excursion
If you go to magnaflow.com or even flowmaster.com you should be able to check fitment guides for each vehicle and compare what years come up for a particular system. Banks Power may be another good source to check into. The Excursion only had one generation so there was no redesign from 2000-2006 when it was put out to pasture. I'd bet it'll fit without any major issues. Perhaps others will chime in.
'00 Durango R/T 360ci 290hp (modded); 138,500m
'06 Pontiac G6 GT 3.5L 220hp; 44,000m
'12 Chrysler 200 Limited 3.6L 283hp; 13,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!