will a 4.i fuel inject motor from xe fairmont 84 fit straight into a 87 falcon gl at the moment falcon has carb 4.1 or do i need more things to fit

physically yes

you will need to have the head fitted with hardened valve seats for it to run on unleaded, and you'll also need all the unleaded ECU, injectors, AFM, etc

honestly, it's not worth the effort considering how much of a pain in the a** XE-XF EFI is

have whole xe fairmont efi car s**t body good motor,have whole falcon gl carb fed s**t motor good body what else needed to transfer motor to good body xe to gl both 4.1

whatever