I have a 1990 wheel horse classic model # 31-12KE01 and need to replace all 4 tires. The sizes are 15x6 8 NHS on front and 23x9.5 12 NHS Rear. I'm wondering if anyone has any specific tire they have purchased and found to be reliable? I have an acre yard with a few hills but nothing severe. I've looked at Carlisle, Marastar to name a few. Also do most folks keep the same rims and take them all in at one time to a local tire garage to have them mounted or just buy new ones with rims? Is having the correct size shown above all I need in order to make sure its an exact fit for my tractor?