OJ, Awesome looking bikes there! Some great thoughts come to mind as I look at them.MC, I could see a big old triple tree on the front of that; with the fatty intact! There is a company down here in Phoenix that makes extra big cruisers. Might check out this site for some ideas...
http://www.bigvintagebicycle.com/
You are right about the triple tree plans. Some 1/4" plate should be strong enuff for me...