Hemi block size

[Gullwing]

I have a fiberglass kit car that I am working on. It presently has a plain vanilla small block Ford with EFI. I would like to put a little "class" under the hood. I have been able to get some info as to which block is which but I am confused. I want to put the largest displacement "small block" hemi I can fit in my engine compartement. The Dodge Red Ram and the Desoto are the two that come to mind. Does anyone have any measurements of the physical size?. I understand that the 276/291 are the same, and that the 330/341/345 are taller. So I am assuming wider. I don't know what dimensions these are though. Surprisingly my biggest limitation is front to back. My front pulley is against the steering rack and my heads are against the firewall. So, I know the Ford block is my limit. I could save some space but using V-pulleys on the Old Hemi but I do so like the serpentine belts so will challenge myself to keep them.

Greg