Sorry dude! I thought this was a Rover thing ?
Have a word with Paul at Whengparts !! He will cut your header flanges to your specs. You can send him a drawing or he may even have your header flange profile on file for his CNC machine.
I got him to cut my flangrs for the Rover and then bought some bends and some straight pipe and cobbled my soomies together for the MGB.
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