Hello and thanks for any help
Before you ask had a black/silver 2000 GS500E I bought in 2001 with 1025 mile and sold the next with  2700. I just picked up the same bike with an engine that the timing chain went and took out the top end.  I just got a 2004 GS 500F with  3600 mile and want to swap engines.
From reading here thing I know
The newer engine will bolt up with no issues
Tach is electronic, no problem. I am 57 so redline is not an issue . But can hook to coil negative if needed or change tach guts.
Oil cooler was added. No problem Fab and welding skills.
Questions
Newer has tps can I use old carbs?
What about the ignition system and spark(coils) Do I need to change the coil packs and flywheel?
Anything else to do?
Thanks
Papa Mann (Papa means old)

Carbs are all interchangeable. The thing while it looks like a TPS, and plugs in like a TPS is really not. I've run all 3 versions of the US carbs on my 95. You can leave the TPS unplugged if your harness doesn't have a receptacle for it, makes no difference. You're running off the older ignition so its advance curve is dwell based (aka pure rpm based) and it doesn't use the TPS in any case.
The ignition is a bit of an unknown to me. I've not swapped those between generations (TBH I've only had 89-00 bikes, yes parts off the 01-02 and 04-09 like carbs but not whole bikes or even motors).
The 89-00 had 2 pickup coils and a wasted spark type of ignition. Like a lot of older bikes did. They waste spark into the exhaust as it flows out. Basically fire at advance angle before TDC regardless of the stroke. The later models have just 1 pickup coil and use some weird shenanigans. Someone else may be able to throw some light on it. But I believe you need the advancer and coil plate that goes with your wiring harness and blackbox. That way also the tach works as it should.
Cool.
Buddha.

Thanks for the reply. I have been marking the wires from the 2004. I will changing out the wires from the 2004 to the 2001. I will try the old carbs at first and see what happens. Another post on here siad to get blanking plates for the hookups from the engine. Manual ordered but not here yet.

04 motor in 00 will need oil cooler ears welded on (or I think these are the blanking plates). Please run the oil cooler.
You will run 100% fine on the 00 carbs and the wiring harness. In fact its easier and you'll have the original cable tach (oh wait a sec, what did they do to that tach fitting in the head ??). They may have not drilled and tapped it - in which case you wont have a tach. You just need the 00's ignition trigger and advancer (which you should have on the 00). Its under that round cover by your right foot.
However you can also swap the harness over from the 04 and the tach. Then run the 04's ignition plate.

OK making it simple. The 04 wiring harness, tach and the ignition plate are married (yes some unholy throuple). The carbs are not (either will work - more unholy references as appropriate). You get a working tach, but more work getting the harness swapped.

The 00's wiring harness and ignition plate are married. Nice holy couple. Carbs are either or. And no easy way to put a tach. Whomp whomp. I think. See if the fitting on the head still has threads etc but the suzuki clowns just put a plug in it ? I know the camshaft has the worm gear but you need the other worm gear that you can fish out of the 00. But it allows for less work from fishing the wiring harness through if you dont need a tach.

Cool
Buddha.