Jack,
Your current question is the same as this one, only without the screenshot set,
https://community.adobe.com/t5/illustrator-discussions/how-to-change-the-size-of-a-figure-without-changing-the-size-of-some-layers/td-p/13301942
Larry gave a fine answer, which can be elaborated as follows:
1) Select everything and scale down horizontally, as you have done on the image to the right, just use Object>Transform>Scale or reduce the W value in the Transform panel; as Larry mentions, it looks like a reduction to about 2/3, which can be done by inserting 200/3% for Object/Transform>Scale>Horizontal, or by adding /1.5 to the W value in the Transform panel (if you use 67% or multiply by 0.67 or similar, you will introduce an unneeded inaccuracy, just let Illy do the calculation);
This scales everything down horizontally so you need to scale everything but the line parts up again without moving any of them from the new position(s):
2) Select all the line parts and lock them (you can Group them if not already), then Ctrl/Cmd+A to select all the other objects, then Object>Transform Each>Scale>Horizontal by the reverse value; as Larry mentions, it looks like an increase by 3/2, which can be done by inserting 150% for Object/Transform Each>Scale>Horizontal.
That ought to put everything right in the right places.
Edit: Hi Doug.
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