Any issue for putting in a larger Radiator ?

I did exactly what you are asking about, and had to drill a few new mounting holes in the radiator support for the new mounting holes in the radiator frame.
A 26 inch went in there in place of the old 19 and as long as your coolant hoses and trans cooler lines hook up right you are golden.

Obviously the bigger shroud will/should be used, but if you do this it will make the cooling capacity much better than it was.