Spotting the difference between 360 & 340 Oil Pan

I can spot the difference side by side, I own and have both installed ( but not easy to get to to measure), but if one comes across one at a swap meet, is there a single easy measurement one can take to verify which one it is, and what is the measurement for either or both?

Make it easy to remember.

Uhhh, doesn't the 340 pan have a smaller diameter rear seal area ????

No
The 360 have the smaller rear oil pan seal to the main seal holder
All the rest of the LA motors,273,318 and 340 motors, have the bigger rear seal

They are the same size both front and rear for 273, 318, 318 poly and 340.
360 is smaller at the rear only...if the ends are different it's a 360...

So from the rear bolt holes, the "LA's 273, 318, 340 have a short space to the drop down and the 360 has longer spaces.
And all the 5.2 and 5.9 Magnum's use the old 360 type pans so long spaces for both.

Words of wisdom, and easy to remember

Here is the difference between them.

Good info! & on a side note there are several 360 pans that I have seen, a 392 & a 876 both of which has a sump ~8" long & the sump starts 4" from a plumb line straight down from the front lip on the 392 and 2" on the 876 & the 876 is needed for a 360 swap into an early A body and they use different pickups, the 392 pickup has a long sweeping bend & the 876 has a near right angle bend. there is a 360 van pan which has 2 indentations in the bottom on either side, not on the sump. #438. EDIT meant to say the 876 pan has the long sweeping curved bend pickup. MORE EDIT its the 392 needed on an early A 360 swap