Sort of trial & error- or rather try & try again. I would spray with hot water and wait 5-10 min ( I don't remember specifically) then try to pull it together. When I couldn't get it together all of the way I tried again. You can use the wires to hold it part way together as you work. I think I also tried hot water soaked rags for awhile. 

I do remember trying several times- including rough shaping a piece of wood, placing it in the stern, and temporaraly screwing the sides to it.

Thanks Ralph,  it went together pretty easily.  I am now trying to figure out how  the transom fits in.  Any help will be appricated.

Coach C.