What are we talking about here, Oilhead, Airhead, or gawd forbid, a brick?If it's an Oilhead, then have a look on the UKgser forum Tech section. Steptoe has a detailed description of taking the heads off an 1150 (I think) ... lots of photos.If it's an Airhead, there are a few PDF copies of the workshop manual flying around the place. Send me a PM if you need any guidance where to look ... If it's a brick ... sorry, not a clue, but I do have a range of hamers you could borrow ... 😀