help :79 GL1000 motor

Following a lot of horrible clanking & grinding noises I may be in need of
some replacement bits for the engine on my wing, however there does seem to
be more GL1100 and GL1200 around and I'd like to know whether I could just
bolt in a replacement motor or did Honda make some radical alterations to
the frame for the bigger engines?

I've not yet taken anything apart so don't know the extent of the damage, I
was doing about 90mph at the time and there is oil in the water and it does
sound 'orrible when turning it over so I'm not very optimistic that it'll be
something minor although it does seem like it's not totally siesed.

Has anyone got a GL1000KZ motor that they could offer me ? or a basket case
with a good motor ?

Allan