2000 Windsor to 01-04 Romeo engine swap

I have a 2000 Mustang GT (Windsor block) with manual transmission. The engine is seized up. I was considering replacing with later model (2001-2004) salvage Romeo SOHC. It is my understanding that fully dressed Windsor and Romeo engines are interchangeable. My plan is to get the salvage motor with the wiring harness intact. Also get the serpentine belt tensioner, water pump, flywheel, and the complete intake from the salvage engine.

Will re-use the AC compressor, power steering pump, and ECU.

I am trying to get as close to a simple plug and play install as possible.

While doing research for this I know the serpentine belt routing is different. Will also need all of the front accessory bolts/nuts from the new motor.

I am confused about the size fuel injectors the various year cars came with stock. The 2000 Windsor has yellow(orange) injectors. My 2003 GT has red(pink) injectors. Some posts state they are 19#. Some say 21#. One post stated the 2000 has #19’s and the 2001-2004 have 21#’s. Obviously, putting 21#’s in an ECU set up for 19#’s could be a problem. Does anybody have any input regarding stock injectors/color/sizes?

Is there anything major/minor that I am missing? Any other parts I may need? Any advice?

The reasons for doing a Windsor/Romeo swap:
Low mileage Romeo engines are easier to find in the salvage yards.
Romeo head have the extra threads in the spark plug holes.
Romeo has the updated intake manifold (metal first runner).

Thank you so much for the reply. It seams that my idea may not have been so far fetched after all.

Should I get the Power steering res from the salvage engine?

Can you help me understand why the original wiring harness should be reused? I have read some post stating there are minnor differences with the oil filter/oil pressure sender. I have also read there are differences in the fuel injectors/connectors. Besides, it is less work to keep the wiring harness the engine came with (I don't mind doing it if it is needed).