How to tighten tailgate on 1984 GMC?

[2badgn]

After 2 other posts on tailgates, I have another problem with my tailgate. It doesnt close great. Sometimes, theres alot of play when its closed. What parts should I change to fix this problem.

I plan on buying a new handle bc its old and cracked.

How do i figure out if i need new trunnions, or cables or hinges or lathches?
I feel like buying a whole new kit but its aftermarket.

What do u suggest?

Thanks

I just want the tailgate to close firmly and not be lose at all.