Mounting RCM battery trays

[Dagger Thrasher]

With my tray, I did it the other way round; drilled and countersunk the tray itself, then drilled/tapped the chassis, and used M4 screws (my tray needs to hold a big ol' pack, so I didn't use the included ones). Aluminium is always going to be less likely to strip a thread than Delrin, so that's the way I did it.