Headlamp mounts.

[Bonzo]

I used a bit of 3mm walled tube for mine .... May be completely barking up the wrong tree !!?? ... But If you are only puting a radius on the outside edge, you'll only need material thicker than 2.5mm ??

You could also choose a size of tube that you can get a plastic end cap for Bop that in there .... that should take care of any radius issues

That said .... I havn't been through the IVA ...... Yet