One of the members of Tekscopes makes new replacement volt/div knob skirts for the 2235. I have bought some of them from him and they are very nice.
He also carries some hard to find good used/tested parts for the 2235 such as the main transformer (T948?), the high voltage multiplier (U975?), etc.
This link shows what he has in stock for sale on eBay at the moment, he must be out of those 2235 knob skirts temporarily.
https://www.ebay.com/sch/shockcore/m.html?item=273836542787&hash=item3fc1ee0b43%3Ag%3AHUcAAOSwZQRYf5YX&rt=nc&_trksid=p2047675.l2562
He is a great guy to do business with as his 100% eBay customer satisfaction rating shows.
I have bought several sets of his new replacement 2235 volt/div knob skirts and they work perfectly.
About he only way you can make a mess of the knob skirt replacement is to  use too much glue.
A few very tiny dabs of glue/epoxy at the smallest diameter of the knob register is all you need, and there is a notch that orients the skirt to the knob just like the original had.
The member name he uses on Tekscopes escapes me at the moment, but you can contact him through any of his eBay auction pages such as this page for his 2235 main transformers.
https://www.ebay.com/itm/Tektronix-120-1601-01-SwitchmodeTransformer-for-2213A-2215A-2235-Oscilloscope/273836542796?hash=item3fc1ee0b4c:g:bAQAAOSwnrJbfX~4
tom jobe...