Another pull start to electric swap question with a twist

[birdup]

I have a complete 1987 30hp Yamaha 30SH that I want to convert to electric start.
Here is the twist. I have a 1989 30hp 30ELF powerhead with a bad crank that I was going to get the parts for the conversion from.

So the big question is will they work?
Will the flywheel swap work or are they weighted different?
Will the harness for the 30ELF work on the 30SH or should I just add to the 30sh harness?
Is there anything I'm overlooking?
Has anyone made up a parts list on this or done a writeup on how to do it?

Any and all help is appriciated.
Thanks

[boats.net]

The parts should swap over with no problem between a 87 and 89 engine.