Frame swaps can be great work. We had a contract with the post office to swap ALL the frames on their Jeep things. They would flatbed 2 over at a time, and a pile of frames. They also supplied a couple things they wanted replaced during the swap, but it was otherwise just straightforward unbolt, lift the body, swap the stuff side by side, roll new chassis under the body and drop down. 1 guy with an occasional helper, day and a half without really rushing it.
Now, Karl can attest that a collision frame swap will almost uncover something overlooked, but a good tech can certainly make out on what a frame swap pays.
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Bryan-NW 'burbs 1972 Malibu Vaguely stock appearing, and the opposite of restored. 1999 std bore 5.7, Vortec heads, Holley Stealth Ram, GM cam 700R4, Viking coilovers, 12 bolt 4.10 posi, and a whole bunch more