Engine bolts

I am trying to take the cylinder head off to replace some gaskets but I can't find the right tool to undo the engine bolts.
I have bought all the possibilities I could find. The correct one being a spindle head M12 socket but it is too stumpy to fit in the gap to get to the bolts, I need a long one.
The only long ones I can find are too small or too big…

Any ideas????

Which engine do you have, 1.1 - 1.3 small block or 1.6 - 1.8 big block?

It is a MK1 golf cabriolet 1.8 engine

M12 spline tool worked on both my 1.6 and 1.8 heads.
I've got a kit like this as there is also a spline tool for the drive shafts.

Extension bar is also needed as the bolts are low down, make sure the heads are clean and all the oil is out of the bolt or the tool won’t sit all the way in the bolt

I had to use an adapter to use my torque wrench as that's 1/2 drive.

Socket Sets & Ratchet Sets | Halfords UK

Do you have a picture in case someone has used different bolts on your head?

They should look like this.
https://www.ebay.co.uk/itm/10-x-VW-Golf-MK1-MK2-1-6-1-8-GTI-1979-1992-Cylinder-head-Bolts/162665163670?hash=item25df996b96:g:Lo4AAOSws1ZZss28