Using urethane (or polyurethane) ends is the way to go on sway bars. Car will respond better on turns and hardly (if any) negative effects.
Once you have your dimensions – I would encourage you to use a Grade 8 bolt with a steel sleeve (steel pipe, cut to length) for it – for better strength. Front sway bar end links have more stress involved than rear ones do – so this might not be a major issue, for you.
I can't remember how many front sway bar end links I broken on my '67 Satellite, '68 Charger, '69 Road Runner and on my '70 Chrysler until I upgraded to grade 8 bolts and steel sleeves.
The front end links are not the same design on FMJ's – but now I have a problem with FMJ front center links breaking.
Maybe I just need to drive less violently, err, nope not gonna happen.
BudW