are the oil oil dipsticks for a 318LA and a 360La the same...interchangeable?

yes you're good

Ive never had 2 of the exact same length.

What i do is change the oil on level ground. Run the engine enough to circulate the oil and then let it sit for a little bit. Now when you pull the dipstick out, mark the "full" level and scribe it with a grinder or drill a tiny hole there.

You can measure down and mark the 1 QT low mark as well....

As long as you use the corresponding tube. Depending on the year engine, make and model the sticks and tube lengths vary. If your tube is the same length as the one you removed the stick from then you should be good to go.

thanks guys