here's what u need to do bro:
-smear NEW ATF on the inner driveaxle splines.
-clean up any dirt or rust around the seal area with a damp lint free rag.
-turn the inner driveaxle retaining ring c-clip so the opening side faces straight down.
- hold the axle as straight as u can with both hands and slowly slide it in, u may have to rotate it a little as u slide it in to lign up the inner axle splines with the inner differential side gear, then brace yourslef and give it a firm shove in.
- u can hold it straight in and also use a polyurethane dead blow hammer to carefully hit the outer axle shaft where the nut screws on to. just be sure the axle is straight while u do all of this. keep at it man, it just takes some patience and practice but it will click in if u shove it in straight