Almost never do I tell someone that what they want to do is ill-advised but in your case I think you are making a mistake. The size is fine and I have crossed in smaller boats but the choice of boat and your route is the problem. I donít have too much regard for the Mcgregor 24 as an offshore boat for several reasons. First, the weight of the boat is too small. You will have problems carrying the added weight of supplies. Second, the rig isnít very strong and you might have trouble with it in severe weather. Third, the hull shape doesnít lend itself to heavy weather sailing and you will not be able to have the windvane steer during bad weather and you will take a beating from the violent movement of the boat. Also a long trip upwind will be tiring and you might make a faster more comfortable crossing by arcing north and following the wind. Can you use a different boat and re-plan the route?
Good luck and all the best,