I checked the shape of spaer which was re-machined with two half inch mirrors at output port and folding port.
The beam can pass through the spacer and the reflected beam can come out.
Therefore the shape seems roughly O.K.

The next step is that gluing the fused silica mirrors to mirror holders for installation of the folded cavity.

In addition, I installed a post and a translation stage in TEM00 path for mode matching lens.
I will continue installation of the posts and stages for other beam paths.