Conversion to 124cui S&S

Hi @all, have the opportunity to come cheaply to a used S&S 124cui. Is of course tempting to upgrade his softail with it … but the following considerations about this: My softail (see profile picture) is BJ 1989 with original primary/coupling, transmission and engine. Conversion to 200 tires. Ignition Crane HI-4. Do I really need a new ignition (Original S&S ?)? Coupling must be … Brakes also new? Holds the frame? Will the transmission…? Would you make it? My tendency is Don’t do it, I think there’s more theater behind … Greetings, Kiri PS: if someone else is interested in the engine, send me a PM….