I have a 1965 Standard, and it still has the reserve tap. I think that was the last year for them (don't quote me), as the 1966 models came out with the 1300 engines.
If yours is a 1965, does it have the glove box lid, chrome on the dash, fuel gauge and full head lining? If so, it would be the Deluxe model.
If not, it would have the reserve tap, but could have been modified over the years
If it ain't broke, fix it till it is!
It was just a tap not a tank and they stopped in 61 on deluxe models when they got fuel gauge as standard.
The 62-67 base standard/custom models had the reserve tap still and no fuel gauge,
if you have 65s with a reserve tap they will be standards not deluxes.