Any visual signs of SP1 vs. SP2 or is there a VIN number on the engine and a way to look it up to verify the year or similar? Thanks for any info ...

Any visual signs of SP1 vs. SP2 or is there a VIN number on the engine and a way to look it up to verify the year or similar? Thanks for any info ...

Oil cooler is different. What's the story behind it?

Buying engine to put into a UTV. Seller is unsure of year but thinks its either an '03 or '04which means it should be an SP2 but just looking for something to verify. Did a little more research ... the D shaped exhaust port rather than 0 shaped on the SP1 should be a dead giveway correct, or am I not understanding this change?

At the rear of the engine, below the exhaust port, you'll find the engine serial number.
It will start with SC45E-2xxxxxx. The next digit to the right of the 2 is the year number.

So SC45E-20xxxxx is a 2000 SP1 (first SP1 year), SC45E-21xxxxx is a 2001 SP1.
And SC45E-22xxxxx is a 2002 SP2 (first SP2 year), and so on.

If the exhaust ports are round it is an sp1, if they are D shaped it is an SP2

If you have the throttle bodies the sp1s are 54mm the SP2 are 62mm

The bottom end differences are internal, like clutch and crank.
Serial numbers are good indicator though!