Hi lone wolf,
In my last address I took the more literal translation as lonesome.
Because with this "model" you are 'einsam und verlassen'. I assume you have visited the mssge boards of www.subcommittee.com. Not detracting from this site, they are the granddaddy of sub modelling. Warship and warshipunderway are concentrating more on surface navies in the smaller scales. Talk to Dave Merriman, a pro, who took a standart plastic fleet boat and made a truly wonderful little model out of it. He furnished a building report somewhere. Sorry I dont remember where. Anyone out there, who knows - chime in.
I don't know your level of building skills, but agree it is a lot of work to scratch build a new stern end. I have stopped building models a long time ago, but intend to reenter the fray once more for a model IXC (1:72 or 96) since I cant find one built already.
To your specific question:
I am certain, it is ok to carefully grind off the offending appendage at the stern and build up the resulting holes with plastic filler. Ofc, you dont have to fill the whole stern end with Bondo. That still leaves you with scratch building new shafts, stern glands, struts, props, rudders etc. For that you need accurate plans to scale up or down. I am just not sure it is worth your effort. If the rest of the model is so outstanding in quality, you might go for it. In case of doubt go for one of the other options. Rgds, RB
PS: I had hoped my attempt at dry humor would not be mistaken for sarcasm. :-)