I thought I'd share my version of the G0704 head spacer modification. I use this spacer in conjunction with the spacer block that gets bolted to the base to column joint.
I decided to go with a 7-piece fabrication instead of hogging out an expensive block of aluminum. The finished spacer only weighs 3.2lbs, spaces the head 2.50" further out and looks pretty cool too! It permanently bolts to the spindle head with (6) M6 SHCS. It still retains the 4-bolt fastening scheme around the head pivot. I support the 3-bolt main t-bolts via spacers between the flat plates so there isn't any deflection as the bolt are drawn tight. The center bolt isn't supported so I use it simply add tension while tramming and to keep the head from coming off.
I removed the set screw on the side which originally kept the head form physically coming off the base plate - I felt it wasn't necessary. I added a 3/8 slot at 12 o'clock for a bolt to aid in pulling the head tight against the base plate. The slot still offers +/- head rotation of 12deg. Any more than that simply remove the bolt.
Here are some pics:
CAD:
Attachment 312856
Attachment 312858
Finished Assy:
Attachment 312860
Attachment 312862
Installed:
Attachment 312864
Attachment 312866
If anyone is interested in having one (for a fee), just PM me.
Thanks!
Mike