[ICOM] Serial Numbers again!

[flearl at msn.com]

Hello Icom Gurus:
                    I have an Icom R-71A s/n 04089 that has the newer dotted i logo and is missing the PBT.  My guess is that it is a 1990 or newer model but not sure.  A fellow on the R-71A group wrote Icom seeking serial number information, received a reply that stated "that information no longer exists".  One way to tell approximate date of manufacture is by looking at the logo and if the PBT is there or not, I understand the PBT was deleted after 1989 but was eventually reinstated, anyone know? 
73
Warren NØWF