Replacement floor pan options for 66 Barracuda with 727 transmission.???

I'm getting back to the Cuda project and need to find a solution for full floor pan replacement in my 66. I will be running a 360/727. I may have enough original floor sections to mostly piece together a "stock" floor. But will a 67 A body floor weld in? Will a B body or C body or E body floor weld in and give more room for the 727? I don't want to reinvent the floor. I'm good with trimming back larger floors with minimal mods. I know 64 to 73 Mustangs shared floor and chassis architecture, so I was wondering if Mopar products did too? Any suggestions and experiences with this application will be a big help. I've only just started to cut my donor car in half, so I will need to find a solution soon. Thanks.

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Comparing early A bodies to the 67 and newer cars, the dimensions are very close. The biggest change in the 67 re-design was widening the front frame rails. The basic centre structure of the 66 and older cars is basically the same as the 67 and later cars. I would suspect that a Duster floor would be a close fit, and that the firewall-trans hump area would be the biggest difference, if at all. Can't say that it will fit, but I suspect it will with some mods