Here is the sheet from a block I had checked. The thinnest spots are highlighted. Just FYI.

 

So what bore will you be using now you know that two cylinders have less material than the rest.

 

For now it's just going to be oiled, bagged and tucked under the bench for the future nitrous motor build. I will probably bore it to 4.155 when the time comes. That leaves me meat to go 4.165-4.185 in the future if need be. BTW this was checked at the standard 4.057 DX bore.

 

Can block filling help?

 

It will be filled to the water pump holes regardless for what I'm doing with it. The thinner spots aren't an issue and are not abnormal at all for one of these. I'm fine with it.