Not aware of that conversion. I did the 1996 Eldorado. I believe if you do a conversion be prepared to buy 16" wheels. Also remember to get a 16" donut spare.
I tried to do that on my laptop but I couldn't get my Etch-a-Sketch brand representing three dimensions. Probably operator error.😖
Interesting about the OEM vs aftermarket, thanks.
Way back when I was really into drag racing, I remember a theory that said, "the only substitute for cubic inches is cubic money." That was back in the good ole days when we thought if you could produce over one horsepower per cubic inch you had a high performance engine. 🙂