Hi mate, no need to be drilling holes.
Although what your about to see isn't my car i do have the very same gauge panel in mine. 96 classic by the way. You'll be doing away with the ctr upper airvents. What i like about this installation it's not in your face it looks factory.
Comes finished in any colour you want or unfinished. I worked mine a bit more and sprayed it a graphite grey colour. These are not mass produced items.
http://www.scoobymods.co.uk/teknopod_edit3.html
I remember trying to get hold of Pete at the time was a nightmere. However aventually he did get in touch. iirc at the time he was in the middle of moving so was pretty occupied with other things. If you like what you see give him a call. Real nice chap.
http://www.scoobymods.co.uk/Index.htm
There is another panel ver similar available if i can find who stocks it i'll forward the link to you.