All California Members

[LynnJr]

You can use any year block you have available.
If you use a 2010 block your truck will need to pass 2010 smog requirements.
If you use a 1957 block your truck will be required to meet the requirements of your trucks year and not the blocks year.

Smog and registration in California goes by whichever is newest.
If you buy a salvaged truck and the truck is a 1966 and you spend 5 years putting it together in your garage with a 2010 motor.You take it to the DMV and when they register it and you smog it it is a 2010.

Conversely if you put a 1958 motor in it the truck is a 1966 on the registration and for smog purposes according to the DMV.

Look at the picture of my registration for a 1972 chevy 1/2 ton fleetside shortbed with a 1974 496 engine in it.
Look closely at the month and day of the week when the truck was manufactured.Notice my name is on it this isn't some wild story.