Apologies to the OP for appearing to highjack the thread, but what a great anecdote, a simple cheap and effective old time solution to avoid an awkward problem.
Where will we be when all these guys are gone? Fabulous to hear that it actually works, but nothing quite like fitting a supercharger to tease out those little weaknesses! Clearly can only be done before any damage occurs and I suspect that, here in the UK, by now we may only have fixed cars and cars needing to be fixed. No doubt there could be some raised eyebrows come MoT time.
At the opposite end of the spectrum I recall many years ago seeing a 6 where the shelf behind the seats had been cut either side and peeled back like a sardine can so that the pin tops could be strengthened without removing the body - cheap but just about as inelegant as it gets, no doubt they have more cunning ways to achieve that now.
Good luck to the OP in getting it sorted, I expect the usual suspects will be along soon with sage advice on cost and other likely issues.
Season’s greetings to all,