I just did my strut inserts about six months ago. I was armed with a lot of good advice from the Brickboard, which you already have. There were also some step-by-step directions with photographs in an older IPD catalog I had. I put Boge Turbo inserts into my humble 245DL and have been very happy with the improvement. The strut bearing/mount plates were well worth it, too.

Two cautions that might help you:
1) Those coil springs could hurt you; be extra careful with your spring compressors. In the middle of when I was doing mine, during the spring-compressor phase, I was distracted by something external. When I got back, I started to take off the top nut, forgetting for the moment that I had been distracted earlier before I had gotten the springs fully compressed. I decided to retrace my earlier steps just in time.
2) Don't get carried away with your impact wrench. Just last night I noticed that one of my new strut dust boots was torn and starting to come apart. I remembered that they looked fine when I took them out of the box. (I opted for the bellows type, KYB maybe?) When I saw that it was disintegrating, I thought I must have gotten one boot that had been left on the shelf too long. In reading your post, I realized that I probably did the initial damage myself. I used my impact wrench to tighten the top nuts. The new nuts were "stop nuts," the kind with a nylon insert that holds it in place once installed. Being new they were tough to get on at first, and being driven by an impact wrench the strut shaft itself spun before the nut tightened up. By that point I had already secured the bottom of the dust boots to the strut tube with cable ties. As the strut shaft spun, a lot of torque was applied to the boots, twisting them, for a brief moment, into unusual shapes. That is probably what caused my new dust boots to come apart. I'll be more careful next time. Maybe until then I can find a boot that can be applied with the strut tower in place, like the sort of boots you can put on CV joints.

Hope this helps. Good luck with it.

Steve.