Good morning, kawboy
Traditionally, pastrami has coarse cracked black pepper and coriander seed rubbed on it. Personally, after curing I use a mix of garlic powder, cracked black pepper, coriander seed and mustard seed (both brown and yellow since I have them). I toast the seeds and then break them up in an inexpensive coffee grinder we keep just for spices. I add a liberal coat, return the beef to the fridge for a day or two for the spices to do their magic and then off to the smoker.
The "corned" in corned beef refers to the "corns" of salt traditionally used to cure the beef and aside from salt just about everybody has a somewhat different take on spices and seasonings. While most commercial corned beef seems to be no more than brined beef with a little packet of what looks to be regular commercial pickling spice mix we prefer the cleaner taste of just the home corned beef.
Some folks add peppercorns, garlic cloves, allspice, bay leaves etc to their salt and Cure #1 brine when they cure corned beef. I haven't really settled on just one way of doing that but could post a sample corned beef brine if that would help.
We cover the beef with chicken broth in a Dutch oven, bring it to a simmer at high heat on the stove and put it in a low (275* F) oven to braise. We find that there is much less meat shrinkage that way as compared to stove top simmering. A three pound chuck will likely need 2 to 2-1/2 hours in the oven. It will be done when a fork pushes easily into the thickest part of the beef.