You have to pull both out at the same time.
You have to lift both out, then remove the Main AC from the flywheel. With some gen sets, you can get your hand in between the Main AC cooling fins, between the Main AC and engine, to take out the mounting bolts. Not the 802 or 803. The trick is to remove as little as possible from the front end. Remove the back end completely, use the cherry picker to pull it out, and set it on the ground. Then remove the rear cover on the Main AC, and go from there. take it all off until you get to the engine flywheel. Engines do NOT come with a flywheel. Where the TM was talking about only taking out the main AC, that just what they meant. You block up the engine, and then remove the main AC. But that's only when you do JUST the main gen. Try to only remove things that hold the rear housing to the skid. Remove the wire harness only so far as it connects to the engine. Then stop. The speed control, only until it no longer attaches to the engine. And so on, an so on. Then take the bolts out that hold the rear housing to the skid. Then lift it up all in one piece. You are going to overlook things. Its your first time. Go slow. Do not force anything. if its not coming easy, something is still attached. LOOK at everything twice, and then one more time. Its better then screwing something up. This should be old hat to you. I am just a nag.
A tip, to putting it back together easy. Since this gen set is a bit flimsy, often putting it together is a PITA. The holes for the screws almost never line up. You have to push, and pull, and hammer on it, using a lots of words you cant use in church. So after going through this several times, I went to the tool trash can, and found every broken punch I could find. Then I ground them down so they fit into the screw holes, with a taper. Then when I set the components in place, I started shoving the punches into the holes. No bolts, just punches. When I had punches is several holes, and everything lined up, in went the screws and nuts. Get a shi* load of fasteners before you start the job. All the sizes you need. USE the washers! The skin is aluminum. The screws with ribs on them tear up the holes. If you use the washes, your holes will stay normal sized, and not grow ever larger. I always use a battery powered screwdriver. I don't know what the hel* you call them in English, (akkuschrauber in German!!) but brother, you WILL be glad you did at the end of the day. There are a million GD screws on this set. Make sure your magnet is handy for all the screws you drop inside the set. Remove the side door hinges at the gen set side, not the door side. When you put them back on, get the screws hand tight. Then shut the doors. Use some wedges, or screwdrivers to center the doors, Then hit the screws with the akkuschrauber. When the are tight, everything opens and shuts easy.
Do get the glow plug wires tight, When they are loose, you WILL overheat the wire ends, causing the plastic and wire covering to burn. Take your time. You don't have anyone watching over your shoulder and holding a stop watch. Do take a gander at your radiator. I don't mark wires. I take them off, and look at the wire diagrams to replace them. Why, because if some fool wired things wrong a long time ago and far away, you repeat his blunder. I am a fan of lock tight. Pictures speak louder the 10000000 words. If you think it can be put back together wrong, take a picture. Have the books out for use, read the procedure once or twice BEFORE you do it. If you see something ain't right, fix it. You will never have a better chance to look and repair, then when the whole kit and caboodle is out and on the ground. Do check all four motor mounts for cracks. Tiny ones are not a worry. Big honkers are a problem. Look at the parts manual before putting things back together. Yes, you CAN get done without a handful of "Extra" parts.
OK, I have run on enough.
you have no idea how much I would like to do this job. And as long as we had good rock n' roll, and loud, I would work for free. Well, maybe a beer afterwards.