Yes: I think the only way to achieve this is by transforming each byte into a list of bits.
I have already done this. Now I am finishing designing the read and write functions to work with single (32 bits) and double (64 bits) precision numbers.
Once I finish this work and test it, I will leave the result in this thread, in case anyone finds it useful.
In any case, one thing is clear: in Lisp it cannot be...