Update time again!
So I found a different brand of blocks on eBay and made sure they were the right sized bolts (on the right). These are much better quality than the first brand, the blocks look like they have actually been cleaned up after casting and had all the seams smoothed.
A before shot of the rear suspension
I started on the right side yesterday afternoon. The new bolts were slightly bigger in diameter so I had to make the holes bigger on the saddle plate. The new bolts were 11.5mm in diameter and I only had a 10mm or 14mm drill bit. I thought the 14mm seemed like too big a hole. So I wasted an hour or so with a round file trying to get them to fit. I had to shorten the bolts too, as they are universal length. Managed to blunten the hacksaw cutting the bolts and they ended up still being too long. Jammed it all back together on the right side and gave up after a couple of hours.
I had a think about it afterwards and realized that I needed the holes much bigger than the bolts anyway so that they would wiggle into place so I had a go at it this afternoon with the 14mm drill. I then decided that an angle grinder was a better solution than using a hacksaw with a blunt blade, so I had the right side fixed up in no time. The left side was then really easy as I'd ironed out all the kinks!
Unbolt old bolts, lift up diff, insert blocks
And bolt up with new bolts. It will be that easy if I ever need to change them in the future!
And compared to the front
I've got to tighten the bolts now it's on the ground and then take it for a drive and tighten them again. Proper photos to come!