Engine Identification

[jpbloem]

Hi Guys, please help, I'm not clued up with engines. I bought a 1965 Chevy C10 Fleetside. Someone told me that it has a 3.8L engine in. So I made peace with it. Last night I saw an advert on Gumtree of a C20 that someone are selling and the specs are that this truck have a 4.1L engine. On the pics it looks the same as mine, no difference. Ass far as I know you can tell the two appart. So on my truck's identification plate are the following, if it means anything: 65/c1400/B8-238290, vehicle weight 5000LBS, Front axle max. capacity 2500LBS, Rear axle max. capacity 3500LBS.