What you are suggesting Peter is entirely feasible but I personally I wouldn't use either methods - heating shrinking, if it cools too quickly before the rim is fully home could leave you with a major problem
and like wise with Loctite. The kind of fit required over that diameter could easily jam before the rim is home and you have the same issue.
Hate to say it but JB Weld is your best bet. Make the new rim a good easy fit over with a slight step in it for it to sit nice and square on the flywheel rim. Liberally coat it with JB, push it home to the step and wait overnight for it to set. The only way to get that off would be to machine it off
and there's no worry during the process that it might go wrong. It also will give you nice machinable fillets should you want them
Hope that's of help - Tug