Gidday Nat,
this is my take.
Patrick Racing in the states is the go.
Core exchange? do you want to send your head and barrels for moding or do you want to buy Warrior stuff from ebay states and have them send it to patrick?
The biggest engine without a resleeve is 1780. Not worth any more effort.
Stump up for the full head job.
Cam kit obviously but include the Patrick pushrod covers.
Buy the full Barnett clutch kit.
ECU reflashed to stage 3 by T4Micha
43mm throttle bodies off stratoliner fit with some work required.
cheers Graeme

I managed to get one of the last yamaha kits before they sold out. Cost about 800 to fit it so not cheap even then. I imagine it will be more with having to go to Patrick for most of the special parts now. Are you after a big power boost? Turbo or supercharger kit may be worth a look!

Actually Nikk (and gidday by the way) its cheaper than the yam kit. Patrick that is. The cost is increased some by having the heads done but even so.
And the heads really should be done, it needs it.
Check prices online, your exchange rate is different to ours.
MT01 stuff is listed alongside warrior stuff, if it doesnt actually say MT, then dont.
To explain about the pushrod covers, one, they look really good but also they "lift" to give access to the pushrods which are adjustable (patrick ones).
You need to do this during assembly, its fully explained in the cam kit, to bleed down the new hydraulic lifters which come as part of the kit.
When I did mine a set of barrels already done with rings and all came up in an ebay search. It was from Orient racing in the states, just a lucky bit of timing, they had one for a project that never happened so my good. So, you never know---------