Just do the Ch*vy upgrade. I did it right before we got all our blizzard weather here in Colorado, from back in december through last week, and it kept me nice and toasty. 78 1/2-ton pick up truck blower moter & squirrel cage. You need to do some minor cutting, but if you have a dremmel & barrel sander attachement, it can be done in less than 45 minutes and is a HUGE improvement.