After running my new KV-1 for a bit I noticed that the drive shafts were going to need some support. One of the drive shafts was quite wobbly and with the close proximity of track to hull I noticed it was binding at times.
Looking around on the internet I noticed some people were removing the drive shaft covers from the hull and putting in bearings. Tank Modellbau also had some solutions, such as the one shown in the attached picture.
Given issues such as not being keen to pull parts off my now fully painted model, or knowing which of the 2 available sizes of the Tank Modellbau parts to buy, I did a bit of research then visited Hobby & Engineering Supplies and came away with the plastic bushes shown in the other photo. These particular bushes have an 8mm internal diameter (which fits freely over the Heng Long steel gearbox drive shaft), and a 10mm external diameter. The 10mm external diameter is a little bigger than the holes in the hull but this was solved by removing the gearbox and opening up the holes in the hull a fraction with a 10mm drill bit. The bushes can then be slid over the drive shafts and press fitted into the hull. They've done a very nice job at taking the wobble out of the drive shafts.
For anyone wanting to purchase these bushes, you can get them from
http://www.hobbyparts.com.au the part number is BF00800-01000-0150-H.