So for my civic (d16y8) I planned on using the d16y8 s40 trans and swapping in a 4.06 final drive but I since decided that I'm probably gonna do a awd conversion so Im wondering if I could swap the gears from the d series transmission and the new final drive into the s22 transmission? (I know dumb question)

 

No. You can use custom gears from MTM and an MFactory helical LSD, but not any other OEM gears. Both the MTM gears and MFactory LSD are available from me at Whoopee Doo Racing.