What year was the original Jensen 75 alcohol fired made? This is the one that looks like a 70 with no smoke stack and used a alcohol burner for heat source.
1950's, and replaced in '60-61 by the electric #70
Was believed to have ended in '59 but I know Gil has a box dated 10-25-60 that contained one of these.
I've had two of these, one with a basic tag and one with an electrical tag. The darker based one (basic tag) is an early restoration from a wreck, I added brass sheet under the firebox to prevent scorching. The lighter base (electrical tag) was sent off to MikeTheNerd in MI.
I found the burner poorly listed with a scarce MM1 vap. burner and another kerosene burner for $20 on ebay a few years before finding the engine. It was unfired
https://youtu.be/jHNw49_Rs2E