Battery vent hose routing.
 

I'm told it's an easy thing. I can't find a hole that routes out to the bottom of my 84'.

There is none, just leave it off or let it just hang downward

I drilled a hole in the body side....

grab an agm battery and never worry about a vent hose again.

I also drilled a hole, put a grommet, then ran a hose as far as the bottom of the windshield washer tank, far from any body sheet metal. I was a bit of a pain ....I dropped the washer tank to gain access. Those battery vents will let acid and fumes out, over time will cause damage. Of course for $$$ you can buy an Optima.

there are lots of agm batteries out there, not just optimas. this is the one i have used for the last few years with no problems at all, including leaving the door open one night and draining it. it's $80 shipped.

Kinetik 600 Watt 12V Power Cell KHC600 - Newegg.com

if you used to have a/c and now have a metal panel filling the hole where the blower was, that's a good place to drill a hole to run the vent hose. that's what I did.