Tranny Swap questions

Hi all, I'm wanting to switch trannys from 727 to my factory 904.I will get the 904 rebuilt with all good parts of course.My questions are...What linkages will I need?And..Has anyone done this and noticed a difference? better? worse? same?I know the 904 is about 50-60 pounds lighter than the 727.I will also get the stock 904 converter rebuilt. Thanks in advance!:salute: