You could define your configuration like this:
Mapper.CreateMap<PartTwo, PartTwoViewModel>()
.ForMember(dst => dst.PartInteger, opt => opt.MapFrom(src => src.Integer));
Mapper.CreateMap<PartTwoViewModel, PartTwo>()
.ForMember(dst => dst.Integer, opt => opt.MapFrom(src => src.PartInteger));
UPDATE
Here is the commit where ReverseMap
was initially implemented. From what I can see in the code, it only creates a simple reverse mapping. For example, in this case it would automatically configure the equivalent of:
Mapper.CreateMap<PartTwoViewModel, PartTwo>();
To get anything more complex, I'm afraid that you're going to have to configure it manually.