Really depends on what wheels you want to run... almost every Porsche had different size and offset rims, so the mods needed to make them to fit a Beetle change.
If Fuchs are your preference then you're in luck as they're pretty much the easiest to get one.. at least ones from a 911 are... because all you need is standard discs or drums that have been drilled for Porsche 5x130 stud pattern. For example that's how I fitted 15x6 ET36 front and 15x7 ET23 rear Fuchs rims on my Beetle - looked great, no clearance issues at all and completely legal.
To fit other styles and offset rims the mods needed are going to be different, and you may need an engineer approval.
If you know/have the exact rims you want to run they'll have the size and offset marked on the inside face...
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'70 Hillclimb Bug 'Jezebel' w/- Haltech EFI -
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'60 KG Coupe - resto kinda started
01 New Beetle - gf's car, but I turn the spanners