I’m just installing a bottom bracket on a road frame and it seems to need a spacer but not sure which side to put it.

It’s a 68mm BB shell and Bontrager Race Xlite chainset, the previous frame it was on had no spacers (2005 specialized Tarmac) and I assumed this would be the same but there is a 2mm gap on the non drive side when I torque down the crank arm.

Which side should the spacer go?

The one that gives the best chain line?

I’m a dumb ass! It needs a GXP (SRAM) bottom bracket not the hollowtech one I’ve been trying