right now i'm starting a 63 chevy short wide on a 97 Tahoe chassis. no problem its done all the time. some people think this kind of stuff is not accepable. But I also have a 57 chevy on a 2005 progressive chassis, a 31 model a on a 2004 rodster shop chassis and nobody thinks this is strange. The end result is the same, Modern suspention and related componants under a old body. and besides the Yukon/Tahoe chassis is just a pickup chassis. most of your fab. work will be in the core support area.