Chip. I changed the front ones on my 49. Can't say it makes much difference but my lever shocks were leaking badly and getting them rebuilt is very expensive.
I found an old chassis that had lever shocks and took the upper and lower brackets from it. I also measured the location of the upper bracket on that chassis and made a drilling jig in cardboard so I could put it in what I hope is the correct spot on my chassis.
I drilled the holes and used grade 8 bolts to bolt it in place.
My rear shocks are even worse than the fronts were but are still on the truck. I have rear brackets and a jig to locate their position but have yet to install the tubular shocks.
If I had my druthers I would have kept the original lever shocks. However at $150+ each plus shipping and the obvious taxes and duties (even though they are my shocks) to Canada made the conversion the alternative.

1949 Chevy 1/2-Ton
"Sedgewick"
In the Gallery
1989 Caprice