NEED ADVISE-Which Upgrade should I do first?

[TJR]

I wish there was a way to tell?

If you want a ballpark figure, you can count the # of rotations of the driveshaft compared to 1 rotation of a rear tire. For example: If the drive shaft turns 3 1/2 times vs 1 rotation of the tire, the gear is roughly a 3.55. A more accurate method would be to count the # of pinion and ring gear teeth, but that would be a lot more work.

A 3.73 is a good street gear. That's what I used for over 2 years (even in the snow), now I wish I had gotten a 4.10.