CAT C15 Acert Injector Cup/Sleeve HELP

[revlimited]

Hi I have a 2007 Freightliner Columbia with a MXS cat engine. I am replacing the injector cups/sleeves. I ordered the cups using my serial number, however the one I pulled out is a different serial number.

I was given 263-4920 from the dealer, however I took out 227-4239 from my engine. When side by side I notice a millimeter of difference. On the cat website when I enter my engine serial number both cups say "Verified part-to-equipment match."

What do you guys recommend?

https://parts.cat.com/en/catcorp/263-4920
https://parts.cat.com/en/catcorp/227-4239

MXS83337