What model combineIJ Ours is a 94 model R62. Would have upgraded if we could have grown anything over the last 10, currently going on eleven years for us and a definite 11 years for a lot in the OZ grainbelt. Our approximate technique follows which is with only a front end loader to extract the rotor. Others may have better ways. Put the auger out to prevent damage to before you start to remove anything. Unbolt gal cover sheet and fold down. Remove belts and one chopper idler.[ Trying to remember this as I didn't get near the machine last year as it and Rolf did little more than a scenic tour of the paddocks before going back into the shed due to full on drought. If that act is repeated this year then you may be able to buy a good used R62 after January ] Undo inspection plate and chock under rotor to prevent it dropping when the road sign outer plate is removed. Unbolt plate leaving rotor naked to the world! Slide a sheet of gal or tin 18" or so wide under the rotor to enable the rotor to slide out with out catching too much. Wind concave right up to support rotor as it comes off gearbox spline. Use a couple of bars through the cage to slide and jiggle rotor a fair way out of the cage. Now front a end loader or equivalent with a good hay prong or pallet forks or similar is needed. We have done the following both on top of and under the rotor Place fork into space between bars of rotor. Chain the rotor firmly to the fork and around the central tube. Carefully lift and juggle rotor to prevent catching on the cage and reverse out with rotor. Balancing after rotor mods; We were lucky to acquire a broken gearbox spline shaft from an N7 which fits the R62 rotor spline receiver. If you can get such a spline, hang onto it as you will use it every time you remove the rotor. If not, I would suggest that you get a foot or two of shaft machined down to be a good neat fit inside of the splines in the receiver. As little play as possible here so the rotor does not sag on the shaft to get a good rotor balance. An alternative here would be to make a stand with a bearing and maybe a neat fitting sleeve over the bearing and into the spline receiver and then slide this stand and bearing into the spline receiver. No sag that way. Bolt the road sign plate back on. Either a large free running bearing on the shaft to support the splined end or make up two small bearings in a V [ on a stand of a height that makes the rotor level with the end plate on ] and nest the spline into them and to turn freely. When given a gentle turn in either direction, the rotor should roll on or back freely to the heaviest spot. A good set up like this which is pretty cheap, can indicate out of balance to a point where a standard bolt washer fastened under a bar bolt or onto the spider plates will slowly roll the rotor. Scrupulously clean All residues from every part of the rotor and backing bars before balancing as you are just wasting time and effort if you don't Spread any balance weights along the rotor as this is static balancing only and not dynamic balancing which will costs heaps. Unless very badly unbalanced, dynamic balancing of an open centre combine rotor other than a brand new one, is probably a waste of time as material lodges in behind the bars and throws the rotor balance out anyhow.