Building a high performance slant engine

I plan to learn how to make all the measurements that I should of done on the slant that is in my truck ( my good truck ) before I sent it in for re-build.

When I pull the head back off that good engine/truck at least I will be familiar with what I am doing cause I have already done it here.

Lets say I wanted to build this engine ( see this thread http://www.forabodiesonly.com/mopar/showthread.php?t=278292) for more performance/torque I guess I would need to find its compression ratio ( first ? ) which I can do by measuring its deck height and chamber volume, does that sound correct?

This way I can know how much to shave off the head.

I have printed and saved Dusters ( From slant.org site ) instructions on finding chamber volume but I do not remember seeing anything that went into any detail on measuring deck height.

Is it just a matter of laying a straight edge across the top of the block and measuring how far down the top of each piston is at TDC. '

Do I need to measure all of the pistons this way?

What other measurements will I need to come up with assuming I am building this engine for performance/torque?

Thanks for any help guys.