transmission transfer case ??,s

[stan79chevy]

my th350 is dead and the 203 isnt to far behind. i want to put in a 205 transfer case and either rebuild the th350 or go with a 400. i can get a th 400 2wd for free is there a way to change it over to 4wd? and if so would the length with a th400 and a 205 be the same as a th350 and 203 case? so i wouldnt have to buy driveshafts. and who sells the best cheap rebuild kit for the th 350? would i need a shift kit? and any other parts that i may have to buy that i dont know about yet would be helpful.

i dont want to get half way in and have to spend alot of extra money i wasnt planning on

thanks
stan