Ok, so I ended up using way less base gasket than i thought. Putting a thicc helping of Dykem blue on the spacer and tapping the inked spacer on the gasket paper worked really well. I've gotten it down pretty well.
If you don't have a punch set, you are doing it wrong. Makes so many holes so easy. I used to punch the base gaskets and to open the holes on the head gasket and exhaust gasket from this to fit. it was lit. Also note: that flange is angled so i can mount it the best orientation to fit the pipe. i think it's gonna work well.
Initially i had cut a .5 and .85 gasket. I could barely measure the squish (@ ~2mm) with no head gasket (.5 mm). So i made 2 more at .3mm. The total gasket stack (including head) ends up a 1.1mm. The base spacing was (4.5+.6 = ~5.1mm) Probably closer to 5mm once compressed. and i may have taken some material off the spacer at some point but it's likely negligible.
Anyways, that leaves the squish at about 1.7mm the piston ring is just barely visible at bdc; the compression is right around 120psi. I'm kinda butthurt how low it is, but it will probably run forever if all goes well.
The top end is comically larger than the bottom.