th350c to 700r4 trans swap help

[crackajacka]

ok ive got an 86 gmc 1/2ton 2 wheel drive truck with a 350 in it(with a edelbrock performer carb on it) and im wanting to swap it out for a 700r4 trans. ill be needing better mpg to get to work and some schooling. what rear end would ya'll recomend for this also. my gf is bout 8 1/2 weeks along so i need to get this done sometime soon plus this one is slippin and engageing late n hard as hell lol. but id like to hear ya'lls opinions, btw mom n dad are helping out with getting the 700r4 level2 from 700r4.com.

thanks

Paul