any advice on what product and/or techniques to remove the residual adhesive from the engine compartment after removing the rubber insulation pad?

3m adhesive remover

goof off and elbow grease.

I tried goof off, 3m adhesive remover and then a scraper. Then I ended up with a wire wheel and ended up having to prime and paint it. Major hassle.

That is what I am trying to avoid.

This is simple. What new surface do you want??

If paint, then fuck it and take the big ass sander to it. Power tools with abrasives all the way. Then prime and paint. (I went with the hammered finish paint)

If you prefer fabric or something, then who cares, just re-glue the new material to it.

If you encounter rust, then obviously that needs to be treated first.

+1

It takes time and multiple applications, but works.

In the trunk I just went for it with a HF grinder with wire wheel attachment.

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