Movement holder for 321 vs 861

Hello!

i have just embarked on a journey to restore a 321 movement and while looking into the peripherals, some questions have popped up.

Can i use a 861 movement holder with jewel support pins on a 321? (are the subdial jewels in the same location on 321 vs 861)

Could anyone help out with a part number for the Case clamp screws? Failing to find the number on any of the PDFs on Cousins.

thank you very much and excited to be apart of this community!

Continuing my journey on the 145.012-67SP and I'm a bit confused and hopefully someone can chime in and help out

My example did not come with either of the pusher stems. I looked up the manual and found both the 1757a and 1758a parts and ordered them.
View attachment 3087651
The ones I purchased appear to be "new" styles but do not engage the pusher screws or are even able to be installed. (The Reset Zero pusher fits but is too short and does not engage the Pusher pin/screw and the Start/Stop pusher stem is too tight of a fit to slip over the operating lever post as well as too short)
In another thread there was discussion around 086ST0059 vs 086ST0007, and the 0007 looks like it had a longer pusher screw. Curious if these are related to the gap but photographically my pusher screws does appear to look correct and match other 145.012 examples I see around the net.

I'm trying to make sense of when/where are these parts used as they are marked as 321. It also seems that a specific 1720 Operating Lever would be paired with this 1757a pusher stem (as it the hole diameter was too small for mine) and would also require longer pusher screws to engage.
It seems then the proper pusher stem is a 320 1757a & 1758a (which i have seen in other threads, but assumed (never should do that) that the 321 marked ones would work as well - alas back to ebay and find the correct parts 😀
View attachment 3087663 Were these parts ever used in any 321 movement based Speedmasters?

Thanks for any responses and sharing your knowledge!

Thank you for the response! i'm looking for a movement vice/holder for working on the movement.
One in question is something like this with support pins: