Re: 54" deck choices for 455 tractor
I have not done this specific model but I have made many different decks fit different machines in the past. I will give my process / tips.
First, I do my very best to find the closest matching deck that I can, same cut size and all. To start, you want the spindle drive pulleys almost in the exact same places as the old deck. If you go bigger or smaller deck size you have to remember that you could find yourself really messed up belt / pulley wise.... I have come to find that welding on deck hangers from an old deck onto the "new" one to be the easiest task when building a frankenmachine. This task is almost impossible when you don't have an old deck to cut the hangers off of and pulleys to transfer. When I find the deck I want to use, I will try and transfer everything good from the old original deck to the new one. Most of the time I use a large piece of cardboard to transfer bolt holes and the mount locations from one to the other, that way everything stays square and it is a fairly quick test to see if it will workout. Take pictures of both decks before removing anything so you can reference them if needed during the process. If your mounts end up being in a higher or lower section of the new deck, don't forget to modify their height accordingly, otherwise there might not be enough or any adjustment to fix the difference. I will use two pieces of angle iron welded together to make a pulley mount if needed. A hole can be drilled in the middle of it to mount the pulley and the bottom sides of the angle can be modified to the contour of the deck before welding in place. If there is a large plate that all the pulleys mount too I will try to cut it off an move the entire plate to the new deck. Make small tack welds to mock everything up first then after you are confident that you got it all right and everything goes up and down right, move on to finding a belt that works. Start with trying the stock one and going larger or smaller if necessary. Try not to rely on the tensioner to take up slack, if it is too tight it will eat belts, if too loose the belt will jump off under load of cutting heavy grass...
I hope this gives you and idea of what all is involved and maybe helps some.... Just sharing the simplest version of my experience.