7 minutes off and 10 minutes on, so not a big deal really. Interestingly the pre 2000 models have 2 extra large bolts, so do take a couple of minutes more than the post 2000 models.
However the facelift has 2 more small bolts than the post 2000 models, so it's swings and roundabouts really. As long as the bolts all undo correctly, then it's not really much of an issue to remove the under tray.