It all depends on the particular connector's state. The "adding mechanical support" approach will only work if the contacts are in place and not bent, and the covers are just not "springy" enough anymore to stay in place but are not entirely crumbling - the external supports only cover the part of the side covers that remain exposed when the plug-in is seated, i.e. they mainly just hold the covers in place.
The transplant approach which I have documented on ("obscure"?) TekWiki was necessary in an extender that I had and in an early instrument (a 7503), where a number of contact fingers were beyond salvage, and some of the covers were cracked too much to create contact pressure even if held in place. It's a lot of work and the modern connector has much higher friction and insertion force (not designed for frequent insertions I guess), but it does conclusively fix contact problems. The contacts de-solder very easily and without danger to the multi-layer PCB, because the holes are relatively wide (I suspect they were slightly oversized by design to help assembly). You may be able to salvage covers and contacts to fix one of the remaining sockets like in my case where both V slots needed replacement but I was able to fix the H slot.
BTW, at least once the contact fingers are off, you won't feel sorry about cutting up the remaining connector skeleton to hold the new connector.
