Bottom Bracket Axle Direction?
 

I was an idiot and pulled the adjustable bracket out to service the bearings. One side is very slightly longer that the other. Is that the drive side most likely? :(

50/50 choice , many cranks need asymmetric BB, and the long side is drive side.

Most likely. If there is printing on the center of the axle the axle is oriented correctly when you can read it right side up with the right side of the spindle in your right hand.

Ah yes, that is how I intalled it thinking that was likely standard.

There's an easy way to check if you've installed it arse-about...

Just compare the gaps between the ends of the crank arms and chainstays.

I've only come across on bottom bracket that was intentionally installed with the longer end toward the non-drive side and that was an early '90's Trek MTB with very fat chainstays. All the others have had the longer end toward the drive side.