i have a c-13 cab. myself ,
like 6 sq. ft. of floor space and i run a 250 hps in it w/ a 19.00 4in. inductor duct fan pulling the heat out of the hood and exits outside of the cab, and another 4in. duct fan pulling heat out the top of cab. like a chimney so it pulls fresh air in thru passive intake holes near the floor. and i can keep temps in the hi 70's low 80's .
peace