I had really intended to use the stock exhaust manifolds, but after 53 years, they were in pretty poor condition. Dual exhaust was hanging from them, with little to no support, which caused both manifolds to have a broken tab. The other holes were drilled through with bolts & nuts in them instead of studs. Not being able to find a good set, I ended up grabbing a pair of the replacements from Rockauto. There wasn't a country of origin listed, but I'm sure they are probably made in China. Oh well.
When I was looking at the exhaust manifolds, I saw that they had a Y pipe, so I grabbed it. Unfortunately, the pipe from the Y pipe to the muffler was not available, or it would have made my life much easier. I took the Y pipe to my local muffler shop & had them weld a bung on for the O2 sensor. And when I went to put it on, that's when I ran into my next snag. The pipe would not go all the way up to the exhaust manifold on the driver's side without hitting the oil pan. That's when I remembered it would have had a heat riser originally.
A couple nights later, I was on fleabay looking for a heat riser, when I found a heat riser delete block. Perfect, it was just what I needed!
I put the correct longer studs in the driver side manifold, added the riser delete block, & the Y pipe fit perfect. Added the O2 sensor & plugged it up.
