Most upholstery shops will tell you that you can't do this at home. So here's how to do it. The info is from an Oct 65 build 66 San Jose Hardtop, with the seats made in the Los Angles area. The same basic procedure applies to 67.
I haven't found a source for the spring strung burlap so I made my own. The burlap is no problem, the wire is a hard drawn steel wire 0.035 in dia and music wire is a good substitute. My current source is Granger -
http://www.grainger.com/Grainger/PRECISION-BRAND-Music-Wire-3L569 I've seen a couple of different ways to terminate the wire ends: a wad of 2 inch wide, real cheap white cloth strip with the wire hooked in a 270 degree loop; the same as above but with a burlap strip; the wire ends bent back about an inch and then with a 1/4 inch dip to lock.
Mark the new burlap with white chalk every inch lengthwise and across. There are about 17 wires on the bottom so make 17 lines across. The back has 15. Use the number of wires from your seat. Make a loop in the wire at one end and feed the wires up and down from the bottom each inch. When you're done with the first one, attach the cloth strip at each end to keep it in place. Repeat with next wire and terminate ends.
The actual seat assembly is in the 66 Interior assembly.
Please include year, model, plant and build date on future posts, so I don't have to look up what your car is in your profile
Jim