Best, in my opinion, is to drill 2 holes to undo the front bolts of the tray easily. That way when it needs to come off its not totally seized, just almost seized.
In my experience, it's better to remove the sump guard once a year to do the oil change, and grease the bolts when it goes back on. Not doing so will normally result in the situation where the bolts simply refuse to undo when needed. It takes 5 minutes, 10 tops to remove well maintained sump guard fixings. So it add little time to an oil change, and gives to opportunity to grease the fixings for the next time it needs removing.