Lynn, as far as I know, all holes fits each other and are lined up (its not placed properly on the picture No.4). I would still say it's original.
There are no square holes in the rear hull plate (see pic.)
No unfortunately I don't have these books yet, because Vol.2 (which would be most useful for me I guess) is not available now. But checking ebay etc. regulary
She's totaly "mystery lady" - no data plate, no T number, there are even no hull numbers present (on the common places). Definitely was built in late 44-45, most parts have a code "BMB" on it (if it can say something) and that's all...