Automatic antenna Coupler  (tuners)   some information I have collected, hope it helps 

OK here's some info about the Collins 490T-1 Tuner
This is from the F1FRV web,,   you should check out  his very nice web.   F1FRV web
490T-1 Antenna Coupler  FULL service  Manual
490T-1 Antenna Coupler FIELD service
490T-1 Antenna Coupler Parts List
AN/ARM-109 Test Set Calibration
AN/ARM-109 Test Field Service
AN/ARM-109 Test Set Full Parts List
Collins 490T-1 Maintenance Manual Abstract

Information about the 180L-2 and 180L-3A  from G3YNH , 
a possible tuner for the 618T  but only work up to 22mHz.

490T-4 Antenna Coupler  Instruction Book   from 4X4RU

There are other tuners, like the one that works with the MRC-95 jeep,   I still need books ,,   do you have anything you can ADD to this info
send it to k0ip(AT) thanks

A Note about PDF's. when you view a PDF they are on your computer,
you need to save them.  in ADOBE Reader, just go up to FILE,
and SAVE AS.  Make a folder,  probably best in My Documents, 
save all the files to that folder.  They are yours forever,  even if I drop
dead and this web disappears, you still have them. consider
making a CD or put them on a memory stick.