[Tamar]

Windows
As is common with Sideways their windows come with nicely prepainted window frames.To mount the windshield and rear windows you need to follow a specific procedure that requires both a delicate touch and some applied force.
As show in this youtube video posted by "Mr Shapeways"? For the windshield you need to insert the upper part of the windshield up from the inside,
slot the tab in the body roof opening and then push the bottom of the windshield in place over the pins under the bonnet.

The windshield comes with the nicely detailed wipers already mounted, some excess flash here which can be tricky to remove without risk of scratching the glass...
...but a bit of making tape and a set of side clippers did the job.

Rear Window
As shown in the video the rear window is mounted from the outside, start with mounting the bottom side, sliding the windowtabs in the body slots is easy, but then. comes the trickier part.
The only way you can mount/slide the top window tab in the body slot is by bending the roof up and pushing the window down. This delicate and force part I mentioned earlier.
Its do-able, I've done it a dozen times now during my test fitting....but. I did trim the top edge window tab a bit so it required less roof bending/ tension to pop in.

 
But...as where the bottom of the rear window fits nice and snug and follows the body, the top end of the rear window does not.
At first I thought I had done something wrong or I had a bad part...but after doing some web surfing, each and every picture I've found of the Sideways M6 GT3 (including their own install youtube video)
shows the same problem. All the top corners of all the rear windows I've seen mounted, stick out above the roofline. 

 
Again as with all the other nagging issues, it's fixable. You can glue in the rear window in the body surround's, but this will add more tension to your body...
..and there's always the risk the window corners will come loose in a crash or a (digital) rear-ender.
You could apply some strong gaffer tape on the inside of the body to pull/keep the top window corners down, but you would still be fixing something you should not have to fix in the first place.
Of all the little items that needed care on the M6 GT3 white kit...this for me was the most annoying.
This is not a quality control issue, this is a design, or at least a production flaw!  

I managed to cure the problem without adding tension (litteraly) but would not advice my solution to de done by those who are building their first white kit...
..as it requires firmly taping down the rear window corners in place...and curing the body with the rear-window for 30 min in a 75˚C hot air oven:o 


Side windows
At least no fitting or mounting issues here, the one piece side windows fit like glove  But while where dotting the I's and crossing the t's... some paint tips.
Below is a good reference picture on how the side windows and their window frames should fit on a M6 GT3 body



To match the body to those nicely prepainted window-frames, it looks much nicer if you also need to paint the recessed part of the body visible behind the side-windows.
And while you at it, depending on the  livery/car you want to make, in some cases (as like with Schnitzer car pictured above) the satin black extends  beyond end below the kit window.


There's a very subtle line on the white kit body (as visible in the top image) that depicts the edge of the area needed to be painted black.
For those that have sanded that away I've marked the area in the bottom picture. 

Below you can see the result, its purely a cosmetic thing, but  I.m.o. the extra black increases the window visually which improves the somewhat "Roof chopped" appearance of the Sideways M6 GT3.


Radiator detail?
Last item on the list of parts to discuss, and most likely also the last part you will mount to your kit body...this rather large, over designed but still badly fitting Radiator support detail.
All I can say is why? With all the decisions Sideways made to adjust the dimensions, go lightweight and use the minimum of material..and then they add this lump?
Its quite a complex shape to produce, so they needed to split it up in 2 parts, which were in my case glued together with a extensive gap, its heavy and you'll hardly see most of it once mounted.
The time and costs to produce this part, would have been spend better on a more detailed interior, with a properly positioned driver.



This determines my rather lengthy review of the Sideway M6 GT3 time to round things up with a final conclusion.

Right from the first publicity shots it was clear that this kit had lots of potential,  I do have to conclude that the M6 GT3 white kit does have its fair share of "issues".
From the proportions chosen by the 3D designer, the production tolerances in the injection moulding process, to the quality control of the shipped white kits.....
[i]Given their track record with the Gr5 series and the wonderfull (more complicated) Huracan GT3, it could have been so much better. [/i]

I can only hope that the feedback posted here will be incorporated in future Sideways projects like the Ford GT and the Ferrari 488

Still, I believe that the general slotter will be more than happy that at least there now is a competitive race-able BMW M6 GT3 out there...
Regardless of the body issues, the mechanical side of the Sideways chassis usually produces good and competitive results.
And that is still the main "raison d'être" for the Sideways M6 GT3, its a slotrace white kit, not a model kit.

With kind regards
Tamar