So, yesterday I started cleaning the block to put on my new heads and found these numbers on the top of the block rail 05yfz020.

I am guessing this block has been decked by .020 of an inch on that side in 2005?

I plan on measuring the difference in the gasket thickness between that and the other side today when I get home from work.

Input welcome!

Also what is the gasket number I need to order for the thicker gasket?

Thanks again