Tailgate alignment / adjustment help please

[Luke87gt]

Hi guys,

The tailgate on my ‘69 looks to be a bit misaligned.

If you notice, the left side needs to come up about 1/4” and the entire tailgate needs to be rotated clockwise by a degree or two, if that makes sense.

You can see there are larger gaps on the bottom left and upper right that need to be corrected.

Having the never done this, I’m wondering what built in adjustment exists for addressing the problem. Thank you.