Increasing Workbee Z axis workable height?

Hi guys,
Let's see if anyone could solve this question.
As far as I know the standard Workbee has a limited workable height of 47mm, Instead of those 47mm I need it to achieve at least 85mm or 100mm max.

From Ooznest at first they told me:

To extend the Z-Axis actuator you can buy a 500mm C-Beam Rail here: C-Beam Aluminium Linear Rail Extrusions – Cut To Size
And a 540mm ACME Lead Screw here: ACME 8mm Lead Screw - Ooznest | Kits, Parts & Supplies​

But three days after they told me:

Just increase the Z-Axis won't work, as it doesn't not increase the relative distance between the underside of the Z-Axis and the spoilerboard. The only way to do it is taller Y-Plates which we don't offer, or raise the machine up with aditional blocks.
For the block, you don't actually need them additions to mill 85mm. To mill 85mm you need to increase the relative distance between the top of the spoilerboard to the underside of the Z-Axis. To mill 85mm, this distance would need to be 170mm. The best way to do this is attach your spoilerboard to you workbench, and then raise the machine up 40mm using wooden blocks. This would increase the distance to about 174mm enough to mill 85mm.​

The suggested solution seems does not seem very sturdy indeed:

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I'm pretty sure that the squareness of the X and Y axes will suffer and therefore the precision of the milling. It really does not seem very sturdy to me.

ANYONE COULD HELP ME TO ACHIEVE THOSE 85 MM OF WORKABLE HEIGHT?

THANK YOU SO MUCH.