deposit built up on AL block

Hello,

It's a very clean looking car and when me and the wife took it out for a test drive, it was love at first site. Just got a 04 Mustang GT 4.6.

The engine had only 20,000 miles when we got it. The Ford dealership, JFK Ford, Feasterville, PA kept the motor clean by steam cleaning it. But now the block has all these deposits on it. Not GREASE!!! Is there a cleaner out there in the market that can get my motor to look brand new without painting it. I could go out there with my finger nail but that would take forever. There easy enough to get off, I just want to do it in a quick, non hazardous way of getting them off, I have no garage.

The block is aluminum. So if you tell me soap and water is good enough then so be it. I'll be outside with a tooth brush cleaning.

Thanks