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Freshly bored and honed 6G74 block, bored from 93 mm to 95 mm to take the 6G75 pistons.

From that I can confirm that the 6G74 and 6G75 blocks are the same deck height.
I've had the same crank, rods and pistons dummied up in both blocks.
I don't have the correct bearings yet so it's been dummied up with old ones of the wrong size so there's a bit of slop in everything.
At TDC the 6G75 piston sits flush with the deck or possibly 1 mm down.I need bearings first, they're on the way.
Then I can turn back a couple of pages to try to figure out the CR using the measurements there.
I might even do a bit of grinding on the spacer plate too , maybe a 45 deg angle so it's bigger on the bore side than the head side?

For the 6G74 stroker, I've now got main bearings and big end bearings.
 
At TDC the 6G75 piston is 2 mm down the bore and at BDC it's 93 mm down the bore.That confirms a 91 mm stroke.

Need to work out the various possible CRs.
95 mm by 91 mm gives a swept volume of  645.111 cc (3870 cc)

Going back to about post no 53 for some numbers. 

Head vol 46 cc
thick head gasket 4 cc
Space , 2 mm, above piston at TDC 7.5 cc
Total chamber 57.5 cc
CR = 645 + 57.5  /    57.5     =       12.2
Which is a bit high unless you're on E85 or methanol.

So that's what the 3 mm spacer is for.
I don't think I've actually checked the hole size yet but lets assume 93 mm for now. About 20 cc.
Also add an extra head gasket, a thin one, 2 cc.

This time.........for CR
Head, 46 cc
thick gasket, 4 cc
Thin gasket, 2.5 cc
Spacer 20 cc
Space above piston 7.5 cc
Total, 80 cc
CR = 645 + 80 / 80 = 9.0      which is pretty much what I'd like.

But what about 2 thick HGs?...an extra 1.5 cc.......8.9.

Having a 95 mm bore and 93 mm spacer plate  2 mm above the piston  at TDC will give a bit of a squish band all the way around which is hopefully better than having a 95 mm spacer.