[Desertwndrr]

What cams? What headwork?

The reason that I ask is because the valve reliefs in the stock cast pistons may be a bit small if you are going to larger valves.

103 to 107 isn't that much of a difference until you factor in that most 107 builds have bumped up compression. You're likely going with a flattop piston, .030 head gasket and maybe a touch off the heads to get to 10.25. Am I right? That being the case, flattop to flattop 103 to 107 won't matter much.

 

[Desertwndrr]

Not really worth going to 107 unless you have to. There are no base gaskets, instead there are O-rings. Personally I'd just leave it and not pull it apart for new rings. If you ever do start to leak down the road, then I'd bump it to 107 and rering it. Plenty of my friends are running upwards of 50-100,000 miles with no issues of leaking and burning oil. Besides, to rering it you'd have to rehone or deglaze the cylinders and then you are looking at having to break it all in again. Save the $$.

 

[Desertwndrr]

I wouldn't pull them up at all. Doing so may break a seal and cause a leak. If the bases of the cylinders are not leaking then do not disturb them. Bolt he heads on and run the piss out of it.