very ls newbe. please help advise opinions options?

[travlinman]

Hey guys I'm very new to this ls swap thing (like last week). I have a 91 r -30 crew cab dually with a tbi 454/700r4 combo. Power windows/locks cruise etc... Motor is toast was ran without oil. So I have a opportunity to get a 04 4x4 suburban with a 5.3 4l60e delivered to me for 650. Would love to swap everything including fuel tank and lines. How simple is this swap or how can I make it simple with the parts on hand.? Figure motor and computer harness but how much of it? All underhood wiring including fuse box?
Will I be able to use my stock cluster? Need gas pedal? I really like the idea of the rear tank and since I have to replace the tanks anyways why not? The tanks were drained when the motor went and caps were left off so I'm sure there's moisture in them. Can I just extended my current pump harness to the new rear tank?
Can I incorporate the new computer harness and keep all my power and cruise inside? Can I keep my 700r4 since the 4l60e is a 4x4 with transfer?
Overwhelming. ..
Any advice or opinions on my options would be very helpful
Thanks