Hey my first post on here so if it's in the wrong place I apologise I'll try and keep it simple but just after some guidance really so any help is a appreciated... I have a st202 with a 3sge engine in but unfortunately was involved in a crash so I have another celica which has the 7afe but is misfiring on one of the cylinders now my question is can I whip out my 3sge and put it in the other celica with the 7age engine I know there is some modification required with the engine mounts but my plan was to take the engine with the wiring loom now on the reinstall is it a case of just swapping ecus and fuel pump etc or is it a whole rewire?

this has been covered, read the stickies.

Just take all the harness from the 3SGE car and put them in the 7AFE car.
Are they both manual?
Both have ABS (or non ABS)?

You'll want to swap the brakes over, unless you already have disc in the rear of the 7afe one?