I just bought this 1968 Charger 9 yesterday

and I think the engine is seized. Don't know for sure, I don't have it yet, so I can't verify... but it's the original Tec HH100, and those get pretty costly to rebuild... I'm considering trying to put one of these in it.

Any opinions? Has anyone done this? If it fits with little to no mods, then I think I'm money ahead with the new engine... I've always used original engines, so I've never dealt with trying to make sure everything lines up. I'm not going to be doing this for a while... (the engine is too expensive) but I'm dreaming for the future, and before I waste too much time thinking on it, I thought I'd ask around. I've heard good things about these Honda small engines, and the local rental store has them on nearly all of their equipment, some of which I've used without problem.
So I'm interested in thoughts and ideas....
thanks.