Without modifications is funny. The JBG one fits without modifications to the body, yes, that is true. I bought some EXTRA EXTRA large black bottom radiator mounts off someone on eBay and I used the JBG ones, that are actually Scott Drake and are way too small on top, but if you cut most of them off, they still look ok.My reasoning is to get best radiator I can get. Both of these say they fit without modifications.
And made in the USA is important to me also.
Any radiator CAN leak. But if you buy either of those two, those people should stand behind it. I don't have a lot of miles on my Howe but it doesn't leak and the times I emailed Howe with questions, they responded quickly.I thought the better built (USA made radiators don’t leak).