Five steering wheels that suit a BMW E46, the three boss kits that actually fit it, and the two things people get wrong: the airbag, and how much a smaller wheel changes the steering weight.

Five steering wheels that suit a BMW E46, the three boss kits that actually fit it, and the two things people get wrong: the airbag, and how much a smaller wheel changes the steering weight.

Five MOMO parts cover nearly every Mercedes, arranged by chassis code so you can find your W number and read the hub off it. Plus the 4MATIC catch and the full B-G, MOMO, OMP and Sparco range.

Five steering wheels that suit a Citroen Saxo, the boss kits that actually fit it, and the thing most people get wrong: not which brand, but which diameter, and how much a smaller wheel changes the steering weight.

Five steering wheels that suit a Honda Civic EP3, the two boss kits listed for the car by year, and why on this one dish matters more than diameter. Drawn to scale.

Which boss kit fits a Land Rover Defender, five steering wheels that suit it, and the check that actually decides the part: count the splines on the column, not the years on the V5.