can't find FKA's post requesting battery box info........ so....
My battery box floor was, as usual, rusted in the front corner.
When I did the engine bay refurb, I cut out the rusted sections and welded in 3mm steel plate.
I decided to also include a drain tube to get it out of the engine bay - now piped under sub-frame.
I created deeper angles in the floor to help get the nasties out of there.
The end of the tube was also angled - much in the same way as the engine breather pipe - in the attempt to "draw" anything laying under the battery.
Can't find the pic I want of the finished pipe/sub frame, so you'll have to put up with this one.
As I have stated many times, I cannot weld - but the neighbours will tell you I can angle grind..............
First pic is the sub frame once I pulled out the box floor - I will never use that body deadener again............

Second pic is of the rusted section of floor about to be removed with plate ready for welding.

Third pic is of the "drain tube" I welded in - it runs through the centre of the hole in the sub-frame..

final pix (and this is the one I have to use instead of the better shot) is of the drain pipe protruding through the sub skirt.....

Sorry FKA - can't find the post you sent...
frats,
Rosco