Just remember, like JB4310 said the newer forks have 2 sets of pins so they can fit different size loaders. the older forks only had 1 set of pins for ether the larger or smaller loaders.
In my photo the top pin is for the 200 and 300 loaders. the bottom pin is for the larger loaders. The measurement shown on the tape measure for each pin is from the underside of the hook (catch) where it rests on the loader.
So you should be able to measure that set of forks form the underside of the hook to the top pin (or the only pin if it has 1 set) and see if it is the same as my measurement from the top pin to the underside of the hook (catch).
Did I make this clear as mud?
The measurements should be purdy close. My son was holding the tape while I was laying on the ground to get a good picture.

Hope it helps.