78 sidecar to 76 flh

[fizz]

I just picked up a 1978 Harley sidecar as it came off a 1982 flh I am going to put it on my 1976 flh. Guy I bought it from says I'll need a different rear mount. I haven't been able to get the 2 in the same place yet, as a buddy is borrowing the bike, but if this is true, what does the new bkt look like. Also, what does it take to get a wire spoke wheel on there to replace the cast one? Thanks