I think I saved front differential, but there is some damage.

Long story short the other day I walked out to my truck and noticed a pool of fluid under it. Discovered that the driver side half shaft had pulled about an inch away from the differential and leaked. I had not been in 4WD recently, there was no odd noises or vibrations while driving. Just the fluid leakage.

I needed to drive the truck so earlier this week I pulled out the differential, both half shafts and the front driveshaft. Last night I finally got around to opening the differential and found the below pictured.

Oddly the bearing cap on the PASSENGER side is cracked, although it was the driver side half shaft that came out. So I will need to replace that. Otherwise everything inside looks good. I turned everything by hand and there are no broken gear teeth/wear parks/loose metal.

Here are my questions and be warned I have never worked on a differential.

1. How do I re-secure the half shaft that popped out? There is a small metal split ring in a groove on the shaft bracket, do I just press it back in until it seats?

2. How do I keep it from coming out again?

3. Anything else I need to check or look for before reassembly?

EDIT: TRIED TO LINK A PHOTOBUCKET PIC BUT MY POST COUNT IS TOO LOW.