I have radials on three or
four of my older vehicles.
They drive much better. I don't know
of a problem, there.
On my 1968 Charger, I have Coker redline
radials.
The 55 Coronet and the 59 vette have
radials, but I used later model wheels.
The only concern I would have is if the old
wheels could properly retain radials,
and withstand the different forces received
through them. I feel better with the
later wheels. I'm not after 100%
stock while driving around.
On my low mileage 68 Dodge pickup, I have
the original tires and wheels, but
drive on a separate set of wheels with
radials. I have been known to drive it and
then put the originals on for a
show.
Don't ever mix radials and bias ply tires
on a vehicle and drive anywhere.
It feels like one end is on dry pavement and the other end is on
wet. Squirrely.