How crucial is headstock thickness when installing Gotoh Planetary Ukulele Tuners

[kissing]

I have a nice Vox soprano ukulele with friction tuners.
I think the stock tuners are Gotoh, which are pretty good as far as friction tuners go.

However, I wouldn't mind swapping them out for Gotoh's Planetary Ukulele Tuners as I would find the geared ratio a bit easier to tune with.

Gotoh UPTL-UBBCW Planetary Ukulele Tuners - Set of 4 - White Chrome

These UPTL model planetary ukulele tuners are made by Gotoh in Japan. Planetary tuners are the ideal combination of the look of traditional pegs going straight through the headstock with the precise tuning and non-slip functionality of geared tuners. The 1:4 ratio makes for accurate tuning...

luthiersupplies.com.au

The specs say

• 3/8" (10mm) hole required
• For headstocks between 11.5mm (15/32") & 13.5mm (17/32")

The 10mm hole is not an issue, because I have a reamer that will widen the hole.
However, my headstock is only 10.5mm thick. 1mm thinner than the specs...

Is there no tolerance for being 1mm thinner than what the specs say?

 

[Spicysteve]

You need the standard UPT not the UPTL. They are for a headstock thickness of 10-12 mm.

 

[kissing]

You need the standard UPT not the UPTL. They are for a headstock thickness of 10-12 mm.

Oh thank you!!
I didn't realise the L in UPTL means "Long"!!

I see now that UPT is for headstock thickness of 10-12mm!

Problem solved