I owned a hacked (by a moron) and then restored (by me and my buddy) '63 Fender Electrical Instruments first-run Dual Showman. Didn't say Dual on it yet, guys, but it was 4 ohms to drive a 2x15 instead of a 1x12 or 1x15 with the 'tone ring'.... Mine was really similar to the ones Dick Dale still tours with. I know this because he and I were comparing notes one time at the Northstar in Philly. I'll say this for my Showman, it had a big, punchy clean tone. Almost too big and too punchy. A twin by any other name is just as stiff.... I also owned a mid-60s single showman (8 ohm output transformer) and that sounded darned similar.
This is a ton of Fender Showman driving 2 marshall 4x10 cabs from the 80s for the cleans in in the bridge.... I was probably using this really cool mu-tron flanger or an original issue EHX small stone too.... dirty stuff is a plexi driving a marshall cab