The boss you have the square around is usually cut off or cast without them on the original 383 A-Body blocks.
The block in my picture is not my factory block. No need to cut it off on my car as it still fits just fine with it in place.
Right now I have the 69 HP block you see in the picture above, a 69 HP block from a Super Bee, a 67 Block, and two 70's 400 blocks, all of them have the bosses on them.
It was hit or miss I guess. I have not found any pattern to determine which ones had them.
I can tell you that I pulled some parts from a 70's C-Body one time and it had the bosses, and they were being used to mount the power steering pump. I was surprised to see that.
-Dave
Dave , seeing how close the boss is to the steering box is why it was machined off , it's cast on all blocks and only machined off those that were getting built for A body installation .
As far as why the 440's used a different mount is because the those bosses started toi be phased off the blocks in 69 , some have them some do not , the 69 440HP block I have wit ha may 69 casting date has the bosses , but others I had had did not .
Some one asked when the bosses went away , for 383's they would have started disappearing in 1970 can't remember ever seeing them on a 70 ??? , no early 400's would have them , no 440's starting with 70. But sometime later, I think it was 73 or 74, the mounting for the power steering changed and lower of the 2 bosses on the front of the block returned and they were all drilled and tapped to 3/8-16 I believe, I'll have to look at the blocks I have to confirm that .
The 440 shown above is how all 440's were done in A bodies and they werer done by hand , I had one of these blocks, it didn't have the bosses but had the drilled holes , when I got it I wondered why someone drilled those holes . Later on after I bought my 69 440 GTS and was looking over the block I discovered that it came from a 69 440 GTS that was numerically 6 numbers off from my car, I gave the block to Jim Rhino when we traded cars.
The 440 mount is very hard to find , Dan , ph23v0 repopped the mount a few years ago , I dodn't think he has any left though . One could make the mount if you can find a picture of it , it's basically the A body 383 mount that's been modified , it's opened up some ... bent further apart ... and a piece of machined down angle material is welded to it to reach down to the oil pump boss .
Hope the OP isn't still looking!
