Alan Hale was a big guy. Look how he dwarfs Steve McQueen.

Alan plays a charming rogue trying to outsmart a bounty hunter on a 1958 episode Shawnee Bill.

His character gives his height as 6'1". And weight as 210.
IMDB say he was 6'2".

Did he seem that big on Gilligan's Island?

I've got the original black and white version. He is great in this episode. I believe he calls himself William Poe at first. Then reveals he is aka Bill Poe, aka Shawnee Bill. Both imdb and the show's actual end credits billed him as Dan Poe. I don't think he called himself that or was refered to by that name in the episode. I also have a nice pic from this ep on my website alanhale.20m.com ;)

I agree Alan Hale is great as Shawnee Bill. After all, he snookers Steve McQueen although later he pays the price.

Alan Hale did many Westerns as did Russell Johnson.

I like the gunslinger parody in Ep 1-7 The Sound of Quacking, where Gilligan dreams the town is coming for his duck Emily.
Even Bob Denver was credible as a Western figure. You could picture him as say the jail custodian Festus on Gunsmoke.