78 Velorex 562 on Harley FLT or FXR

I picked up above sidecar and looking to mount it on either my FLT or FXR (both mid 80's EVO models). Total newbie to sidecars.

Will use for occasional taking my dog (90+ lb shepherd) with me.

Everything on SC appears to be factory OEM.

Previous owner ran it on a Honda Goldwing.

I've seen a few posts denoting that suspension should be upgraded on larger bikes like my FLT or FXR. Can you provide details on this?

Are factory "universal" mounts sufficient for occasional use?

Any other suggestions for mounting/running this sidecar?

thanks,