Thanks for the replies (I took it on the chin like a man, Andy). What it's all about is that I sold my old live axle rocket some years ago (big mistake) and bought another chassis with a plan to install a rather mouthwatering X Flow that I'd acquired (roller rockers, 254 cam, '45's, etc). Then work, a few seasons of Clubmans, kids, 'bikes and general decrepitude intervened. The big problem is the SVA - the heart says keep the X Flow, the head says stick in a crate Duratec. When the X Flow block was skimmed it took off the engine numbers so unless I can be creative with a set of punches it's going to be tough to prove it's pre '75. I took the chassis back to Arch and Bruce reckons the Duratec will drop straight in but then there's the tank and loom mods and all kinds of other unforeseen hurdles. So what to do???