The first of these two 1954 Strats is dated March 1954 and it has serial number ‘0108’ on the spring cover. The rumour is that the Strats with trem-cover numbers were actually salesman samples.
They’re often very heavy and the bodies were usually made using multiple pieces of ash, rather than the single pieces Fender did later. The weight difference can be as much as 3lb. I’ve had a couple from January 1954 in the past, but the earliest Stratocaster I currently have pre-dates the ‘0108’ by a couple of months.