Maybe I should look into that Jimmy, thanks

 

SBF's have been notorious for leaking at the china rail ends which were originally sealed with a cork gasket and a spot of silicon sealant at the intake ends. Felpro realized the problem with the cork deteriorating over time and revised the gasket with a rubber gasket to fit the rails. That with a little permetex has always worked for me. I think there are many that have just used a 1/4" bead of RTV on the rails to substitute the rail gaskets. I also replace the dist housing gasket during this procedure. Time consuming repair but easily done.
At the shop I ran we did the oil dye test with the black light but was more a pain to make sure all areas were cleaned before installing the dye.

 

Check the o-ring on the distributor.
For the intake I prefer cork end gaskets. I drill holes in the block and put welding rod cut so they stick out just above the block surface, it holds the cork and I have never had a failure on any of my engines or customers.