Joe Gibbs or Lubriplate(what I like for convential). I also like to add a half-bottle of GM EOS for insurance. You will want to stay with conventional for a flat-tappet cam.
Welcome to CR! Nice dime. Can you give some details on the 408 build?
Remember that this was the first year for the Kissimmee show. I heard there were some pretty great cars there though.
I'd give buckeye unlimited a call. If they don't do it, they should know someone who does.
Buckeye Unlimited LLC
5424 Byers Cir W, Columbus, OH 43229
(614) 846-5811