Thanks for sharing. Everyone has slightly different techniques. For example, I use my tacking iron completely differently. You seem to use the tip to 'draw' lines, where I just put it down flat and slightly move it back and forth on one spot. This seems to be more gentle with the print.
One contribution I like to make refers to the print position on the mount board (see attached). It's called: finding the optical center. I don't use it as a rigid rule, but as a starting point from where to improve the print position further. I also look for even borders (top and sides) as long as the bottom border is always slightly wider than the top.
... Ralph: in your diagram, how do you determine point "0" (or where line A is located)
The ‘optical center’ of the mount makes for an attractive print placement in most situations. To find this optical center, align the upper left-hand corners of the print and mount-board in point ‘A’. Now, bisect the remaining spaces to the bottom and right of the print, creating lines ‘a’ and ‘b’, respectively. Then, connect point ‘B’ and ‘0’, creating line ‘c’, which intersects line ‘b’ in point ‘1’. Finally, align the lower right-hand corner of the print (point ‘C’) with point ‘1’ on the mount-board. The print is now at the optical center of the mount.
If you feel this results in the print being too high or too low on the mount, slide it up or down until you have equal top and side borders, or find a more attractive distribution of space, but always maintain a vertical print offset.
As Ralph says, you may be able to find one for free. Some (I started to say "many", but I'm not sure of this) folks are moving away from dry mounting for a number of reasons. I switched to over matting with the print hinged to the back of the over matte at the suggestion of a number of gallery owners and framers. You can search this forum for this and find the many opinions and discussions on dry mounting vs loose matting. I haven't let go of my press yet, it's a bridge I don't want to burn.
I guess my main point (having not answered your question), is that you might try flattening and over matting prints before deciding that you need to dry mount. It makes the process simpler too.