You are correct that this is telcom equipment.....however,those LSI chips with the gold lids were made to military specification(milspec) standards.I assure the yield will be considerable higher than the non milspec's.Most LSI equipment is made to milspec standards,but not all.Almost all ceramic chips have a little gold solder "pad" under the silicon chip.In the case of your chips,the pad is larger,and thicker than that of a civilian use chip.When you remove the "lids",leave the ceramic on the heat a little longer,the silicon chip will dislodge itself from the pad.Make sure you include the silicon chip with your ceramics,because it will have gold on the bottom of it.
There are also a lot of ceramic "proms" on the boards.They will most likely also have that gold pad inside of them.