Hello.
it's a bit hard to give you a detailed answer, because I don't know the cluster, it's size etc...
but what I would do is buy a couple of TYPE_R tachometer from Ebay and use them to replace the oginal speedometer and tachometer of the dashboard.
TYPE-R tachometers are the cheapest you can find so you are not going to waste a lot of money if it doesn't work.
Regards
Cristiano