Pulled the old girl out to see if she can still dance and I think she did alright. 30 years old, on a rickety mount, loose gears, and wobbling in the wind but she still produced good images. I found some replacement mirrors for $30 recently and had to take her for a spin.
I, for one, don't consider it a true test of the old scope if the parts have been replaced. Especially if the mirror or objective lens is replaced. Even mirror revolting negates "doing xxxx for an old scope.
That the scope as improved does well is a fine thing.
That an old scope does well having only been cleaned, mechanically adjusted and lubricated but still 100% original parts is a different thing and impressive.
I think rather few of the common scopes were EVER properly setup and used in accordance with the included instructions. Certainly Tasco booklets and some others into the 1980s had good information.
There is a reason RTFM became an internet phrase; most people assume they can assemble and operate most anything without looking at the manual ,despite evidence to the contrary.