Chuck, In my opinion, stroking the slant six is not cost effective. Even boring just to get more cubes, is not the way to go. However, with the amount of cylinder wear you will find in just about any slant six motor, boring will be necessary for good ring seal. So you might as well go as large as your budget will permit. Generally it will cost about the same whether you bore 20, 30, 60. after that the price will go up. Selected slant blocks have been bored to more then .150 oversize.
If you still have my number, give me a call, or send me a PM and I will give you my number.
