I was recommended to a person down in devon/cornwall, i believe he's a one man band, thats done work to my friends 205 track car and has done a few of the cars running in the castle combe saloons, and he does a very good job
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He gave me a quote of around £900 to create and fit a custom 6 point cage in my HPE.
"This would be based on a 6 point weld in picking up on the top of the rear turrets, with a criss cross diagonal and triangulating back into the door bars, I have also included a tunnel brace, and plating to the shell where possible."
He's also got a soft spot for lancia's as he worked in a dealership in Italy. Give me a message/email if you want his email address.