2 fans, 1 more powerful than the other, PLACEMENT

Which of the two fans should i use as exhaust. should i put the more powerful fan at top for exhaust or put at bottom for intake?

Paint-can i use acrylic white paint for inside of cab

as for the painnt yea sure why not, and as for the fan i would use the bigger one as an intake and smaller as an exaust

Stronger Fan (Higher CFM) = Always exhaust.
Weaker Fan (Lower CFM) = Always intake.

Assuming this isn't an airtight biohazard room

I use flat white when I paint.