Painting a cast iron block with POR15's Kit.

Here is the kit I'm speaking of:
http://www.por15.com/ENGINE-PAINTING-KIT/productinfo/EPKA/

KIT CONTAINS:

POR-15® SOLVENT
MARINE CLEANTM
PREP & READYTM
POR-15® (Black or Silver pending on Engine Enamel color choice)
ENGINE ENAMEL (color of your choice)
Paint Brushes
Safety face mask
Latex surgical gloves


My question is: I've never used POR15, what is it's consistency? Can you use it as a bondo/filler to get a smoother look than the cast iron? I've got some rust pitting that I'd like to hide.

Cheers, and happy Thanksgiving to you all, well those in the USA!
Drake