HOW CAN YOU TELL IF YOU HAVE A G10 OR G20?

Does anyone know how to tell if you got a G10 or G20 van?
Can you tell by the VIN #? Got paper work with both G10 and G20 notes.
Tried looking online for VIN# finders and all of them are saying VIN must be 17 characters. Mine is only 13.
One of you have this van wizard knowledge?

Thanks so much!!

So,,,,,,lets see if we are on the same page,,,,,,,this site is for the Earlys, the originals, 1964-70, the Vintage Vans,,,,,,,,,without hoods, engines between the front seats,,,,,,,1st Gens were built 1964-66, all G-10,,,,5 lug bolts,,,,,,2nd Gens were from 1967-70, G-10 had 5 bolts, the G-20 had 6 bolt lugs,,,,,,ANYTHING with a hood goes into our Early Enough section, the section for OLD vehicles,,,,,,, so are we starting off on the same page or a different one?

Thanks for the reply! So am I asking this question in the wrong section then? I didnt realize there was a different area to post in. Mine is a '79. So I should delete this post and re post in the EARLY ENOUGH section?
Thank you Donivan!

You can keep going,,,,,,this topic will be moved to our Early Enough section tomorrow because its a 4th Generation Chevy, way different than our 1st and 2nd Gens that we talk about here,,,,,,I surely got a 78 G30 and a 74 G20 sitting in my driveway with 2 1965 G10s. The 20 and 30 got 13 digits in the VIN,,,,,4th letter tells what they they are....

So the model is on the service equipment decal under the hood and on the fender,,,,this is a 74 G-20, you got this on your van or just trying to read what a VIN number means?    

I'm Trying to read the model off the VIN. My van has had the whole body shaved. No emblems.
The first 4 letters of the VIN is, CGL 15++++++++

Thanks! You've been the most help out of everywhere I've asked.

Well that says 1/2 ton G-10 van.....

L means 1/2 ton. 1 is 10, for G10. So if the 1 was to be a 2, if it would be a G20?

You the man!!

The L is probably the type  body style, like panel, Sportvan, camper or step Van,,,,,,,