Keeping disabled products showing in the store

This is one of those things I've played with from time to time but haven't gotten right and cannot seem to find a mod for it.

I would like to keep disabled products showing in the store for seo purposes, but if the product is disabled, I want to disable the add to cart button with something like "No Longer Available - See Similar Products" and highlight the related products perhaps by linking the button to scroll to the related item section on the page or by moving it up higher on the page in place of the original product description.

Is there a mod like this I am not finding by searching? Ideally for v2 and 3 as I am working (slowly) on a v3 version of the stores too.

This question was asked multiple times already and short answer is: you can't. Set quantity to zero and enable products you want to be viewable, but not purchasable.

Yeah that doesn't work for me since I don't keep inventory in opencart and allow out of stock purchases. I would think it would be doable - just beyond my limited coding abilities.

You can simply hide Add to Cart button for those products, which you don't want to be purchased. This can be done via CSS, for example. Kinda fool proof, but easy to do. Another way is to check for product ID right in template and don't display the button, if ID matches.