Ok. I exported the altered beastie as an obj, brought it back in as a morph, did the Freeze ERC thing with the appropriate pose, but I’m having some scaling and translation problems with the final result.
Here’s the result now…. with just a bit of cheating. Namely, I loaded the saddle and bridle, fit them to Horse 2, chose the clone Charger, let the refit happen… and then unfit the saddle and bridle and translated and scaled the horsie to get them back on to the horse. The saddle fit is much better than just repositioning the saddle: the green version is the refit saddle, the pink is the original. The bridle, not so much.
So I’m not going to be posting the process until I manage to figure out what I’m doing wrong here. A couple of things have changed in DS 4.5 about how clones are handled, and I didn’t have translation concerns with my previous clone attempts. But I’ll get it figured out… eventually. 
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