i'm both extremely impressed with and extremely jealous of OP for this mod. i'm curious about your experience using the "L" mode, though. one of my frustrations with the mav is the inability to engine brake down hills at a speed like 30mph or 45mph. if i push the L button at that speed, it...
OP: what's best may not match up with what's achievable if your only option is to street park it.
if you have the ability to park it in a 1 or 2-car garage overnight with AC power available, your best bet is a combination of things people have already suggested: use a wet/dry vac or extractor...
for those (like me) who are finding this thread and wondering what the fix was, it's not page 118 of the manual. it's page 117.
use the steering wheel control to go to menu > display setup, then page up or down to get to a checkbox that selects/deselects km/h speedometer.
it's not intuitive...