Injector thread size?

I have got some spare injectors for my cab but on closer inspection the thread size is bigger on my spares than mine any one know why?
My engine is a k plate  dx and the spare injectors came from a e plate dx

larger thread injectors are early, small thread are late. can change the fuel lines to suit if you like

Hi thanks for the reply I have the fuel lines for the lage injectors if I use them will they fit the metering head ok?

yep metering head is the same fitment, just the injector end that changed