well if you havent' started making your new model,..you can just open the existing one and delete everything except the hair and start modelling...else if you've already made the new model and just want had the hair in,..then on the other model,..(MAKE SURE YOU SAVE AS A NEW COPY BEFORE YOU DO THIS!!!) delete everything except the hair you want to transplant,..and then just go file export,..and select the default type,...then open the new model and import the file you just exported and place it on your model......this should work with most programs