magnum 360 into a 74 duster that had a slant 6

Ok.. Then why does the book for a 95 dodge 1500 call for a 91 gram weighted converter?
'95 Magnum? Didn't see you mention that before. I have heard that the '93-'95 5.9s (OBD1) did use a neutral flexplate and placed the weights onthe convertor, and '96 and later (OBD2) used a weighted flexplate and neutral convertor; the 5.9s I've built were all post '96, so the book MAY be right for a '95 factory setup, I've just never dealt with those years. Just make darn sure you use the right flexplate if you're going to mix'n'match your assembly.