I too had a VTX 1800. It was a challenge to get a seat to fit. It took a Corbin to finally make it work after a Mustang and Mean City tried to fix the stock saddle. The F6B is the same. The Ultimate King Rider was my answer and Kury mini boards lowered the feet. I am 6'1" @ 250 with 34/35 sleeves and 32" inseam.

I think Honda builds ALL of their 800+ pound bikes for 5'8" Asian guys that weigh 170 lbs with 32" arms. Go figure!