The track opens at 4pm Northstar

So I bought a NJV head a while back and set it aside for the future, and I was looking at it the other day and noticed the front cam tower cap had a hairline crack in it. It's not very big, but still visible. Is the head junk now or can I swap a new cap over and have it line bored? Thanks guys.

Went to do the suck test on my vaccum advance and noticed this. Need a little help trying to figure out what this little guy is. Might be the cause of my stumble problem.

I'm trying to find a stock exhaust manifold for my 1986 ESIR, that is not cracked. Maybe its from a part out and you happen to have one. I appreciate it if you provide pictures. Thanks!