That should be plenty - although I missed where you're getting the 75mm from? Do you know if the back end sits up higher with the GSXR linkage? Mine is up a bit with a GSXR 750 swingarm due to the length but I'm not using the GSXR shock or linkage.

My OCD just won't let me rest. No, I am not going to leave painted parts as is. I did downgrade to spray bombs for frame (VHT frame/roll cage). I tried to use it per instructions but still got runs when did swingarm (it's on picture prepped). 
Prepping - I have to sand every bit now. Orange peel from previous prime/paint is too much for my taste so I sand it all down. Good thing everything is dry and not too bad to sand. 

First tried failed with swingarm. Yesterday painted light casings and few small bits - worked much better. Really need to be careful not to create runs. Layer will be thin, but I have 2 layers under, so it should be just fine. I like finish I am getting though. Will do few more practice batches with smaller parts before tackling actual frame.

 

Welcome. I'm partial to the '82 GPz750 myself. Mine still has the stock swingarm but with new bushings and ZRX shocks. I would suggest the cartridge emulators in the front with appropriately sized springs. 

Hi guys, allow me to introduce myself.
I'm Bert from Belgium and I've always been a bit of a Kawasaki enthousiast.
My first bike was a 1990 GT550 and I've always felt bad for selling it.
So now, years later I decided to buy myself another vintage Kawa, insert the 1982 GPZ750...
Unfortunately I'm gonna have my work cut out with this one, cause there's all sorts of things wrong with it.
But nevertheless it's a good base for a project that's been brewing in my mind for years now.

The plan is to start with getting the bike running and trying it out.
If I get everything as wanted, I'd like to take it a step further.
I hate caferacers because they ruin originality and they made classic motorcycles rare and expensive.
What I love is periodic-correct bikes with coressponding upgrades.
I have some friends in the classic endurance circuit and that's the way I wanna go...

The main idea is to get wider wheels and tyres with better brakes and also stiffening the frame up a little bit.
So I'm hoping someone here has tried changing the forks and swingarm for something better with minimal effort?
If anyone can point me to some topics on this matter, that'll be great!
I want a classic looking bike, so no USD forks and monoshocks.
I'm probably gonna have to weld some mounts to a modern swingarm to keep the stereo shocks, but that's ok...
Besides that I might put in a big-bore kit and I wanna paint the bike in KZ750L3 colors...
And the electrics could also do with an upgrade(maybe an m-unit) cause there's been messed about with it a lot!!!

I'm no mechanical marvel but i can manage my own.
And I have a lot of skilled friends plus hopefully the forum's help so I'm optimistic.
It will take time, but let's hope It' end up being as awewome as I'm imagining...
That was the introduction, so please let me know if there's anything I need to know about the bike or the project.

 

05/17/2022 Update - Finally got around to performing Wookie's direct feed to the coil(s) test. With being wired direct I'm getting approx. .6V when cranking and when running is between 1 and 1.4V quite and improvement over running through the ignition. Oddly, it didn't seem to help it as far as starting and running compared to the 2.5 - 4V through the ignition. Pulled the carburetors for another breakdown and inspection. One of the carburetors had a film type gel blocking the tiny port of it's pilot jet. Cleaned and reassembled, running better but wild throttle swings. After a little more investigation with some contact cleaner found two of the carb boots leaking badly where they mate to the flat surface of the cylinder head. For those that are new to this, spraying contact cleaner, starting fluid, etc. around a suspected air leak will make an engine rev like crazy. Ordered a set of aftermarket boots through ebay from China so now back to the parts waiting to come in saga. Ever notice when your working on an old bike just about the time your ready for reassembly there's another gotcha around the corner where you have to wait for another part to come in. 
Anybody have any experience with these boots: item 282802816993 (paste this number into ebay search box)
@Wookie58 - Would you consider the 1-1.4V something to live with?  If not does this indicate a problem with the coils or some sort of back-feed even though wired direct? I'm pretty sure she going to run OK with the new carb boots as it now starts like it should when warmed up. Still a little iffy when cold but with leaking carb boots it makes sense as to why it would be difficult to start when cold.
 

wrote:

GS1100e swing arm? What’s locating the rear caliper?

P.O had 2 lugs welded to the swing arm as the gsxr mount slots in, hope these photos make it clearer.