I did a little reading on 4L60E tranny issues related to hard 1st-2nd gear shifts and light shift slipping issues and found a few sellers with good reputations selling rebuilt valve bodies but I have a few questions. Has anyone here done the swap ? How hard is to to replace the valve body in that tranny ? Is it just a matter of draining the fluid, dropping the tranny pan and removing the valve body ? Are any speciality tools needed ?