Okay so I'm back with an update and some questions about where I am now.
to start off I've replaced the piston rings on all cylinders and installed new cylinder base gasket and head gasket along with fresh head and cams, valve clearances in spec.
So I had it all back together and went for the first ride and thankfully when I came back and took the valve cover off the oil was clear and not metal sludge
drove it for an hour then and fixed a few small coolant leaks and just felt the bike. the carb water heater circuit hose has a tear and just slowly leaks at a constant rate but apart from that there are no leaks now thankfully, and I've heard I can delete that circuit anyways which I might do.
I also found out after attempting to balance carbs for the first time that only 2 cylinders were running... so I was driving parallel twin I guess at least at low rpm.
there is very good compression on all cylinders after valve clearance and new rings and head gasket so I think it has to be carb related issue, it also hunts a bit.. but im chalking that up to me doing a crap job balancing it and I've messed with the fuel screws to try get cylinder 2 and 3 to heat up, turning the fuel screw on carb 2 I got that exhaust to heat up a bit more but 3 is still cold. I checked all the plugs and HT leads and even swapped them around loads of time because I was worried i had them the wrong way around. I believe the HT leads are all fine and plugs are all giving good spark.
It does sound like all 4 cylinders are working well when I'm on the throttle though which is good. possibly just the pilot is clogged. im going to check the carbs over tomorrow and probably remove the coolant circuit from them at the same time.
So I'm probably running rich on some cylinders and lean on others and not at all on 3 XD, carbs are a mess atm but they're my next priority.
I will say even with the state of the carbs at the moment the bikes feels better than ever, even with a shot clutch that needs replacing asap
All of it was done with the engine in the frame also.