Something has moved forward. Let's start from the frame preparation.
Chevrolet caprice frame has 116" wheelbase, my Buick has 122". It needs to be lenghtened 6" in order to be used under Buick...
Thats how that caprice frame looks like. I managed to get station wagon frame, which is stronger than sedan's. It has also additional supports in rear part. It should be strong enough.



You can see here sedan's frame rear. It has open profile and no supports between longitudinal and transversal parts. We will use it's front longitudinal parts.



Now it's time to start (with a little fear) cutting. My friend who has workshop we are doing this said that there are two stupid persons - one that imagined such a project, second that agreed to do that... :)
For starters (apart from measuring, measuring and once again measuring) we need to remove rear part of the frame at the factory connection.



Now it's time to use sedan's analogic longitudinal parts in original places. They will be longer and will allow us to have frame lenghtened.



Several hundred times measuring. Frame is in fact leveled despite it looks tweaked.



After grafting sedan's frame parts we set their proper width and welded them to that grey thing. Now we need to make sure they are leveled, parallel to each other and perpendicular to the transverse part of the frame. Measuring again and again, until diagonals are equal.



After measuring and welding that connections we can remove excess material.



Front part of the frame.



That part was cut lengthwise in order to allow narrowing its profile. That way we can insert front part of the frame into the rear part and weld it on much wider area.



Just like this. Measuring again, of course...



After several hundreds of measures we can weld it for good!



Ready.



You can see in background newly finished inner part of the frame connection.



In next update - floor.

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