I replaced my rear engine isolators, originals, in April of 2022 using Vetus K75s. I put the base into a vise at home. I used an 8mm allen wrench on top of the post. They come apart. Don't overthink it like I did. The post is on with a loctite like product, so once you crack it, away you go. I used the same, blue loctite, when I put the post back on the isolator with the base screwed to the engine joist.
In 2021 I replace the front isolators, originals, with Vetus K75s. I couldn't build up the nerve to cut the rear ones off during sailing season. Yes, it did make a difference, but my port side front original was completely shot, so ymmv. The front took about 20 minutes each side, including putting in new lag bolts. The engine supported itself on three, so really an easy job.
Glenn - if you are still on the hard, let me know.