Stagea NM35 troubles. radiator was more than 3/4 blocked!!

had to perform a few fixes to the stag. may as well upgrade some bits :)
had the idea of making my own radiator top tank, then when i went to blast out the core. almost all the flutes were completely blocked! this old farm rig must have been sitting for quite sometime. luckily even overheating, the engine seems to have held up fine. no signs of oil consumption or coolant leakages. completely removed the thermostat. misfire only comes back once its warm sometimes at idle. and most definitely boosting at wide open throttle above 4k rpm. for sure coilpack.