Martin wrote: “it was almost as cheap and far easier to buy an entire driveshaft with both CV joints for £91 (about $121) rather than buying two CV joint kits and doing all the disassembling/reassembling.”
I’ve been saying that for a while, but then I’m inherently lazy and don’t like axle boot replacement. 
There has been our share of home built cars over here, too, often done as a family effort without the benefit of good mechanic experience. @Alan Merklin has seen his share of those, others, too. And then there are those others built at home that are superbly done. Kind of a toss-up.
Look on the bright side, though, Martin.... Once you finish, it will be done RIGHT! (And then you can be like some of us, coaching others through their build!)