summit and jegs heater boxes

[my454s10]

has anyone evr used one of those heaters that you mount under the dash...they sell for 139.00 in jegs i think...it would not take much to heat my truck..i tore the factory heater box out years ago...like a retard

[tracker]

i put one of those boxes in my wrecker when i was in the military. the original heater in that truck sucked ass when it was night time and 20 below. with the extra bok i mounted under my dash it helped alot.