Resew or glue, redux

I don’t mean to be difficult but I stand by my description of three separate signature. The “pastedown(s)”( a single sheet) actually went from the front cover across to the back cover, all one piece, which ended up tearing down the spine. The three signatures (1)two sheets, folded to folios and visibly stitched, (2) 4 sheets, folded to folios and visibly stitched in center, (3) same as first. Each signature is quite tight, BUT the “threads” which tried to tie them together has stretched out leaving the supposed text block floppy, loose. Residue on spine would indicate, that despite the questionable construction of book, that the original text block was glued to the case down the spine. I know, I know, but I can’t describe it any other way….there was NO attachment of first page as a flyleaf to a paste down….same at the back….? So I have decided, for practice, to remove all stitching, resew, apply either mull or sekishu across spine of text block, lift endpapers for insertion/gluing of mull/tissue. Still requires redoing spine of which there is a shred left. A lot of work for a book I could replace off Internet for $5.00, but the experience is invaluable. Thanks for your time.