Inlet Manifold Bolt Sizes

So this should be a pretty simple answer but for some reason i cannot locate the information anywhere.  Im looking for the size of the inlet manifold bolts for my Mk1 (1989) Cabriolet I think they are M8x65mm but i also see M6x38 listed? The website says they both fit, which cant be true unless it has both? If it has both can you advise quantities please. 

https://www.classic-vw.co.uk/inlet-manifold-bolt-kit-12pc-n90123201--n0147513-12840-p.asp there are 2 different lengths needed

Look like they are out of stock but 3 are m8x50 and 3 are m8x80 use Allen head bolts as tight to get a socket on them

Thanks sporttrucker, will check them out!