mix equal parts of ATF kerosene and petrol, use with a stiff brush and scrapper - nothing beats it - Ive degreased a leaky diesel corolla that had 5 years of grease cakes on it, I think I lightened it about 20 kgs. at least.
The car took 5 days to clean, it was that much of grease.
for the POR-15 - nothing beats it, just clean and paint over, let to dry and voila new part. Literally impossible to buy in Pakistan, best alternative is the rust convertor applied in 4 stages then coated with a primer or enamel paint.
btw - Reezvan please dont insult the car by reusing rusty jubliee clamps - replace with new ones, CNG guys have the best kind but I could buy the small band (OE) type clamps at the Jubliee rubber market in Karachi, they cost about Rs 20/piece but are good for life.
cheap solution is your freindly CNG fitter.
