You can compare the sail dimensions on this site:
http://sailboatdata.com/view_builder.asp?builder_id=52
by looking up the particular model then comparing those dimensions to your particular model..
the dimensions are E, the mainsail foot, the length along the boom
P, the mainsail Luff, the length along the mast above the boom
I, the foretriangle height, from the stem fitting to the front of the mast
J, the foretriangle base, from the mast base to the stem fitting..
There are a few models, so make sure you look at the correct one.. It would be a good idea to measure your boat dimensions to be sure.. The Hunter main may have a very little more "P" but by measuring, you should be able to see if you have the room. another thing to check is how the main is attached to the mast.. slugs and size, or boltrope..