som2002 I am in process of doing this retro now .. Several here have done this and have given very positive feedback on it.. I dont have mine all the way in yet and it will be a bit yet but cant wait..
One thing many here recommended ClassicChevy 5 Speed for the tranny and kit vs Keisler due to their excellent customer support and I for one can vouch for that.. The guys at ClassicChevy are excellent and trustworthy to a tee. I recommend getting their kit. They have been most helpful for me...If only they could get a better name for their company......
http://www.classicchevy5speed.com/