Can a newbie restore a 727 or 904 transmission ?

Hi Guys , bought my old duster back and im very happy , but i think my tranny is dying...but thats not the question today , im about to buy a spare 727 and i have a s6 and sblock 904 , bought 2x books on internet, i never did such a thing , i love my set up and its only a regular 727 / 2800 stall / shift kit trans...all the rest is stock ( internals ) it was rebuilt 12-13 years ago and i was thinking to redo one by myself , dont want to pay 2 000$ for one.