Looked at it this AM... IIRC, the 51009 uses a GM .927" diameter pin. So it just depends on the rods you use. The larger pin is the standard Mopar pin size, and would match up with the standard SBM rod length of 6.123" that you list. Seems logical to proceed on that path.
The SCR (static compression ratio) that you refer to works with the cam and other setup factors to set your DCR, dynamic compression ratio. That is the real determinant of what fuel you can, or need, to use. 8:1 is what I came up with using the parameters that I listed and can be run on pump fuel with some reasonable tuning care. The suggestion for milling the deck block down was to obtain a 'quench gap; that was figured at .039", achieved with the deck milled so the piston tops come up even with the top of the deck ('zero-decked') and using a .039" Felpro head gasket. Effective 'quench' a helps fight detonation tendencies, and helps combustion.
And stop me from blathering on if you know all of this! I just saw that level of SCR, and wanted to check to see where you would end up for DCR.
