help with my 72 4x4?

[myfirst72]

i have a lot of questions,most are probably just no briners for you folks here,but this is my first attempt at a restoration. i just got my 72 about 2 months ago and it seems like the right time to park it and work on it for a while. my first question,is there a kit to swap a 700 r4 in and keep my 205 t case? it has a th 350 now,and my gas mileage is killing me. will i have to cut or lengthen my drive lines if i were to put one in? its pretty much factory except the new ring and pinion and posi as far as i know. just a 12 bolt and 44. also looking for around a 4 inch lift kit,wheres a cheap place to look? NOT 4 wheel parts.