Caterham 160s have a live axle borrowed (and modified) from the Suzuki Jimny. I hunted high and low for something the right diameter and shape to tap the axle oil seal in. It's a tight fit, and needs to be done without mashing up the rather delicate seal. 

Here's what I found in the garden shed:

It's the finial off the top of an old garden table umbrella. Perfect diameter, and a lovely boss on the end, at which to aim my mallet. 

This may be a candidate for a 3D printed product. Group buy anyone?!

By the way, if any 160 builder wants an alternative to Blatchat, there's Big Jimny forum

My building blog here