The only aftermarket full clusters I have seen documented are the KOSO RX-2N and the Dakota Digital.
Other makes have been fitted - but I have never seen the wiring details.
However Kosos are all well documented - If you can get hold of a copy of the users manual (the wiring bit) we can make sure.
Jon at Digital Speedos in the UK is pretty understanding - he might be prepared to copy that page.
So far every Koso I have seen has the same wire colours - which helps. I have a couple of speedos here now.
And they will interchange as they are all to the same standards (unless they specifically say they are for a specific bike).
We also have his electricness
@DEcosse on hand for assistance.
I was doing some R&D - but had to stop in May (I was in the UK) and have not been able to get back into the groove.
To be honest I simply have too much going on at home and work.
Have a read here
An R+D Thread - Different instruments.
If it were me I would get a new set of connectors and NOT hack existing wiring. Mainly because the Triumph loom is bulky anyway.
But I am so minded. It's all pretty much in that thread noted above. Diagrams, wire colours etc. Connectors etc etc.
There are some things you need to add to make sure the speedo sensor works etc - but we can guide you through that.
One question: Do you have a GPS device of any sort? - SatNav or phone. It's going to help when it comes to speedo calibration. No biggie if not.
Also - I would offer this for consideration.
We know that you can muck about with the speedo via the ECU. Though doing so stuffs the ODO reading a bit.
The stock tacho is optimistic. Whether this is the tacho itself or the ECU signal - I don't know.
But with aftermarket clocks you CAN choose to wire them to OTHER speed/rev sources.
Just a thought.