Original looks pretty good. Bet it would be even nicer after stripping the plating. I tried to find pictures of a built one from the kit but the Fotki account they were on is gone and if I saved any the thumb drive they were on is no longer working.
A friend of mine is doing the 70 conversion using the AMT 68 and front end from a Monogram 70 Chevelle. Not much adjusting was required to make it fit. The model looks really good. I'd post a picture but for some reason my computer doesn't recognize files on my phone.
His resin is very nice. I have had the opportunity to see the development of some of his masters. Michael researches everything he does thoroughly and his detail and casting work are some of the best I've seen. Michael is working on something right now that will impress a lot of builders.
No, the only thing close for those years is the AMT 65 Olds Dynamic 88. You could mate the 65 Grand Prix roof to a 65 Olds body, but then you would have to modify the grille and taillights to make a Starfire/Jetstar.