smog ports on exhaust manifold

For now, I'm going to use the stock exhaust manifold on our newly built 6cyl 250. The thing's a 1975 250 and have all the smog BS fittings.
I was just going to put a bolt in the holes and call it good, but 3&4 wouldn't come out.
So I had all of them welded up from the outside.
Now the inside is what have have question about.
Take a look at the pictures and let me know what I can use to fill the inside part of the hole. If it's really needed. I know the smoother the better.
JB Weld, some other high temp filler.

Before you get started on telling me I should of just gone with headers, or go to a junk yard and grab another year exhaust, here's the deal. It's my girlfriends car, which just a quick engine swap has turned into more $$$$$ than expected.
At this time I just want to get it started, break in the cam, and get it on the road. Then we'll do the exhaust later.

Looking at 3,4 from inside


I know it's ugly, but it will do

 

Why Bother to SMOOTH 'em?
That would be a waste of time & effort Slick.
Just like writing this.

 

Run it.

The engine won't know the difference, neither will your girl.

 

yea, run it......you've already blocked the outside from leaking. i used plugs on sbc motors that had the injection tubes and never had a problem.

 

This was my thought, but........
I've heard others say to "waist" your time grinding and smoothing, and making the surface polished.

WTF, it's exhaust......... get that **** out and make room for the next stroke.

Thanks

 

If I were concerned about the inside, I'd just weld them up like the outside. I do like to grind the flashing and ugly blobs off of cast iron manifolds. I just like them detailed.