Right an update for you, The car had the head gasket replaced with the Athena 1.4mm one, which has fixed that issue, and I had my new oil catch tank and braided lines fitted to the new rocker cover at the same time. My new brakes have also been fitted and are A LOT better than the ones that came off! It was rolling roaded just after to check she was all healthy, and despite a bit of a misfire on boost, produced 217.9hp at around 6800rpm, 0.9bar. Despite changing the rotor arm and dizzy cap, the misfire remains so need to check the plugs next. I also had a nail go through one of my Goodyear Eagle tyres so that was another £80 to sort. I'll be attending Practical Performance Car Magazines PPC in the park show tomorrow at Mallory Park, where it'll be doing one of the track sessions in the afternoon!