Yes, you don't need to do anything but remove the old ones and put the new blades on.
Remove the deck from the tractor, then remove both blades. They can be sharpened using a grinder. If you don't have a grinder, then there are shops out there that can sharpen them for you (try asking at a shop that sharpens chainsaw chains).
Yes.
Yes
what size nut is on the blades on a john deere z225 42 in mower
The regular deck on a 325 is 48" with three blades (You can only buy blades in sets of three from John Deere.) The standard blade is 16.6 inches in length.
Turn your blades off.
There are specific store that carry that paticular brand John Deere. You can try searching online for a replacement or in the phonebook to try and find the tire.
There are several online websites that sell replacement parts for the John Deere 3020. You can also check at local tractor stores for parts.
My 345 User manual says replacement plug is (M71939) from your John Deere dealer. Clint
Check your seat safety switch. Just a guess..
John Deere 1010 is a popular farm equipment. From searches onlines the John Deere is a good tractor and has pretty good reviews. Therefore, it should be a good replacement of your old farm equipment.
Do you seriously not have a few to try?!?