Mirror Cap Problem

I Have just bought some new mirrors and a focus lens from Cloudray and the problem I have is that they are twice the thickness of the original K40 mirrors and consequently there is not enough thread to engage the cap. I have temporarily overcome this by removing the small nylon washer on the mirror holders and have engaged by about 1 thread. Does anyone know where I can buy deeper mirror caps?
Duncan

are you referring to the stock k40 head???

The focus head mirror is OK, it’s held in with stock small leaf spring and there was enough play in it to accommodate the extra mirror thickness. The problem is with mirrors 1 and 2, the stock ‘cap’ which holds the mirrors and then screws onto the stock adjusting heads is not deep enough to accommodate the extra thickness of the mirrors. I wondered how others have worked around this problem.
Duncan

I don’t have that problem as I replaced all my mirror mounts.