Welcome to AFM! Swapping in a 351w is done quite a bit... we have that in our 65. The possibilities are endless... you could go full restomod and put a late model 302 or 4.6 in there. There are plenty of kits for doing that and mating up modern tranny's as well. I wouldn't think it would be too hard to find an old 289 somewhere either. I guess it really depends on what your goals for the car are.
Keep us posted and thanks for joining!:bigthumbsup
Keep us posted and thanks for joining!:bigthumbsup