67 PS and shaft into a 66.

[vince1]

About a year and a half ago I found a 67 in the auto wrecker with power steering and a collapsible steering shaft. I bought the plates to mount the box onto my 66 frame and changed out the old single spear shaft to the collapsible D shaft. The truck still has the 66 column and everything seemed to fit into it quite well. I seem to recall something about a 67 shaft could fit into a 66 column but nothing newer, yes or no for the benefit of others? The pump bracket I modified IIRC from an 85 Buick to fit the 230/250.

From searching old threads on PS upgrades there was mention of but no answer as to why the idler arm should be changed. I never did that so am wondering what the reason for that is. Everything works great as it is. If someone could help me with that, many thanks.