With Radial tires I always shoot for as much positive caster as I can get out of the old Ramblers. I think I'm at about 3 positive on the American. That's a ball park number though as I've set it with my handy dandy home shop Castor camber gauge. I go for as much postive as I can get, then I back of to the side that is the lesser of the two. Then set toe at 1/8" Camber I Usually set at 1/2* negative, but that's a personal preference for the windy hilly roads arounf here and tires usually wear slightly quicker on the insides with that setting. I would drive it till the nubbs are worn off and then have it rechecked if it bothers you and see if they can adds ome positive castor and leave the camber at 0*
Wow, that's a lot of caster. But you and Jim pointed out, these things were designed for bias ply. I don't recall what I did on the Gremlin, but the Rambler, well, no sway bars etc it's not exactly a drift car so factory settings doesn't matter. The last car I had that I cared about performance handling was my 79 AMX I used to SCCA SOLO II. I had that cranked lots of negative camber and I forget what else.
If I wait too long they'll charge me to realign (reasonable enough).