My carby bloke(RIP) said they OFTEN got air leaks from being done up too tight. He used to race a p76 in ipra class (Nigel Newman) 

Over 20 years ago the wire on the right that goes to the PTC heater had broken off and it started using fuel at a phenomenal rate, got that sorted and it went back to normal...   These 2 pics show that the gaskets and diaphragms were weeping at the bottom...     Many of the surfaces were warped, so they were faced up with some wet n dry...       The worst surface was the base of the carb body, it was a bit banana shaped (no B4 pic) and took some time to get it nice and flat again, which our former local carb restorer who has now retired said all the Weber's (34 ADM) go like that...    

sure it wasn't blocked with a rats nest or similar? or rust   with the cat, when mine was blocked it was SO HOT, it melted the carpet 

if you can feel heat 30cm from it,  it's likely blocked. 

2000rpm you'd definitely be making a LOT OF NOISE and air flow, so i'd be leaning towards it being blocked by the description. 

Also I forgot to mention that it seems to not put out much exhaust out the tailpipe (even at 2000) you can barely feel it) compared to my f100 with the same engine although I can't tell if this is because of a blockage or the leaks in the system

Well there's been a development. I haven't pulled the cover yet but I took her for a good drive today wide open going 140 and she ran perfect and when I pulled up it idled good but after giving it a rev it slowly lost cylinder 1 again. I noticed the misfire disappears after about 2000 rpm so I'm starting to suspect something lifter. Also it no longer stalls out when I come to a stop so it must have cleared out the atf. Still not to sure about the cat as the exhaust was clogged up with carbon to begin with as it was used as a farm runner at the end of its life. Any way to check or do I just have to hollow it out to see?

That's unlikely, IMO. Keep us posted with what u discover!

Ive got a new rocker cover gasket so ill pull it off and give it a look. Just wondering would the atf burning off would have clogged up the cat?

Could be a bent push-rod also, however you'd usually hear the random ticking.   I'd pull the rocker cover, and idle the engine with the cover off. Watch for anything obviously wrong.   If you know how, I'd use a dial micrometer to measure valve lift on all 12 valves, look for differences in the recorded values.

Well I just got back from taking it for a spin and its terrible. Putting the headlights on is now enough to stall it. I would rerun the compression test but my tester gave up the ghost. At first it ran great but as it warmed up its now just fucked. A this point im suspecting a fucked up lifter not holding when the oil thins out or a wiped cam. I hope its not the cam for this engines sake otherwise its getting a clevo. Real shame for such a low kms engine to be shitty like this.

@SPArKy_Dave I reran the test and it got funky. I had 150 on all except cylinder 1 which was at 110. However this is where it gets funky. I poured some atf down the cylender and when i tested it it fucked my schrader valve. however after replacing it I cranked the engine to clear the atf and whatdya know its back at 150. I only got one reading before my compression tester finally gave up the ghost but now it has me hoping it was a stuck ring. I'm gonna leave it to sit for 2 hrs before clearing it and taking it for a drive and ill update you then.