Yes, it's true! I'm excited to see this progress. I would love to put a Coyote 5.0 or a new Boss Coyote in #1998.
See it here: http://www.svtperformance.com/forums/pics-videos-buffet-149/805322-74-pantera-gts-5-0-coyote-motor.html
Check out the second page for 180 degree headers.
I'm going to attempt to contact the guy doing it and get the scoop. I just didn't want to be the first one if I did do it. The Cleveland will make more power under the curve, but won't be as reliable as this motor will be for sure. Not to mention the power adders that could be employed easily...