I've posted some about this tractor in the past but I wanted to update and document some of the things I've done to it. It is a cub 71 with a k301a from a 122, along with 122 stickers placed over the 71 stickers. Both sets have faded now, resulting in something like 712 lol. It sat for around 30-35 years under the overhang of a barn. I got it running, replaced all the wiring, and added a 38 inch mowing deck from a wide frame. If you have questions about this process, I can help. It is definitely possible and I didn't have to cut anything, I just played around with different hanger designs and slightly reworked the mule drive, mixing parts from wide frame and narrow frame mule drives. This is my main mower now. It is replacing my family's 1554 because I think it is a lot cooler. The majority of the wiring was redone with 4-wire house wire. It works very nicely, but I wish it was 5 wire. Because I realized near the end that I needed to run one extra wire for the headlight power, but all of the regulator and generator wiring is contained in the big house wire, which cleans it up nicely and is much more durable and thicker gauge. I changed the key switch due for a new one if similar design. The headlight switch wiring was quite messed up and peiced together. I dont know if it was wired this way from the factory, but now the headlights only come on once the key is in the "on" position and the headlight switch is engaged. Now I keep the headlight switch engaged always so that it reminds me to shut the key all the way off to prevent the coil from receiving power while the tractor isnt running in case I make a mental fumble or the tractor cuts off unexpectedly, and I dont turn off the key. It acts as a warning buzzer of sorts. Again, maybe that is how the lights were wired from the factory, but I had to completely rewire it so I am not sure, but I like it a lot. The throttle handle is not original and does not fit well, but it works for now. I replaced the cable so it is a little smoother but I want to do more work to it. Maybe I can make the throttle attach to the steering column with a turn signal-style handle kindof like a bigger tractor or a model T etc. I replaced the pto clutch, which resulted in a thread about how much I hate them and they should be better. I eventually got it working well. All 4 tires hold air after all these years of being flat. The seat pan rusted out, so I made a new pan and welded it to what is left if the old one. It is sandwiched by a peice of 1/4 steel so it shouldn't fall off. I had to get a new regulator, as the old one was a hand-me-down from the titanic evidently. The starter/gen started well but didnt charge. Found the feild windings to be bad. Bought a used one and it worked but eventually the front bearing locked up. Super scary because I thought the engine was locked up for a few min. I took the peices from the two starter/gens and made one good one. NEVER try to remove the pulley from the starter/gen unless you have a brand new one to go back on. I used every appropriate pulley puller I had, but it just bent the pulley horribly, then I had to unbend it to reuse the pulley once I realized it would never come off. The pulley is made of very thin and bendy metal. The drive clutch is on it's way out. It was stuck engaged when I started working on it, so I had to pry it apart/rock the tractor until it came loose. Yesterday the column tower finally broke loose due to rust. Now it actuates with the clutch lol, but it still works for now. I plan to fabricate a new lower column replacement and weld it up next. Then I need a clutch. The mechanism works fine, and I am on a very tight budget at the moment, so I am looking for cheap alternatives to replacing the whole kit. The throw out bearing is actually beautifully smooth. Not sure if I can just buy the friction pad or not. Id rather make one out of brake pads or something lol. Regarding the k301a 12hp in the 71 frame, ask me any questions and I will answer to the best of my ability with pictures but I was not the one that put that engine in. It was installed before it was parked 30 yrs ago by a man that is dead now. It doesnt look like the frame was cut or anything, it looks like a direct bolt up. I am going to have to deal with the detent ball or whatever that holds the shifter in reverse. All other gears stay in gear fine, but reverse pops out real easy. I havent found much literature on these detent balls or whatever they are called aside from the fact that I need to get it unstuck. Do I need to split the tractor to do that, or can I go in from the top, like rebuilding a shifter on a car? Sorry this post got a little rambly, I am very happy with this tractor, and I feel like a lot of this information was learned by trial and error, so maybe it can help you along the way. By the way, for now, it runs pretty great, starts with no choke, idles good, but it does seem to have an Intermittent misfire or pop when running at higher rpms, not sure if that is normal with this motor or if I should do some more work to it. Carb has been cleaned a few times tank is clean. Running a 12v mopar coil with no resistor at the moment, I have ran it about 100 hrs like this so far with no problems. New head gasket, but I think I will do it again due to a few pretty severe pits in the block surface. I dont want to machine the block. I guess I can flatten the head with sandpaper and glass, but I am seriously considering filling the pits in the block surface with JB weld or something.