The Exterior of Mopars are treated with a hot coat zinc plating prior to painting at the factory. This coating should never be "sand blasted on the exterior". One guy mentioned a sand blaster attachment for a pressure washer. That is a great idea. It will keep the engine bay cool and keep the surface clean and control the dangerous dust from blasting. I can not remember who sells that pressure washer attachment, I wish i had one. Right after you wash the interior of the engine compartment spray it immediately with a Zinc Phosphate coating and dry the body with a leaf blower and "dry " compressor air. if you need to media blast any rusted areas get Dupont Star Blast XL about 8.00 per bag "50 lbs from a local distributor, this blast media used on a very slight angle does not warp body panels if you keep the pressure low and use a pressurized blaster.
Regards,
Steve
Wild_Hemi