Joined the Early A Club

Even slight toe-out will cause a car to wander. Toe-in can change with ride height (springs sag), so check it every few years. You can measure quite accurately with a tape measure if your tires have straight channels.

10" drum spindles are better than 9" since bigger wheel bearings. Both outer bearings in my 9" drum 1969 Dart spun the race to ruin the hubs. Little SET1 (or A1) as I recall. Both can be upgraded to front disks, though I'd be tempted to switch to 10" spindles first.