anyone used hooker fenderwell headers

i knew the up to 66 and 67 on were different engine bay widths which was the only reason i asked the question. i wondered if anyone had tried them on a later body and if they fitted or how much they'd need altering to fit. small block fenderwell headers aren't exactly readily available these days so i'd be nice to hear from anyone who'd tried them. if it's going to be a real ballache to fit them i'll just make my own from scratch, it would be the first time.
neil.