1999 XJR Maintenance

I recently had to say goodbye to my wonderful MB E320.  Some lady tried to drive a Lincoln Towncar thru it!  Everyone walked away without a scratch but the car looked like a hatch-back.  The good news is that I was able to replace it with a really nice '99 XJR.  I have always loved the XJ's and the anthracite/ charcoal combination is absolutely stunning.  I was a regular on the MB forums since I am a DIY'er with decent skills, so I was glad to locate this forum as well.  My questions are:
1) Niksail or no Niksail: I have read "worry about it" and also "XJR didn't use it".  
2) Is there anyway to verify if the tensioners have been replaced without a disassembly?  I didn't know if there was a method to visually verify the parts: lights, mirrors, action!
3) Transmission:  Car has 137k on the clock.  Original owner (to about 95k) kept excellent maintenance records, but the second owner was not as vigilant.  I cannot find any evidence the tranny was ever serviced.  Should I have the tranny serviced?  I had just spent 4k on the E320 tranny so I know how that part works.
 
Looking forward to getting to know the car and the groupies, Thanks for your help.

Welcome.

1. No nikasil
2. Remove cam covers. You can see secondaries. Timing cover removal for primaries.
3. If never drained, leave it alone. On the bright side, it also has a MB box. W5A580

Thanks Factory.  Are there any resources available for the DIY'er on some of the basic repairs and maitenance?  I have a CD with the service manual on it but I have found it's good to get some of the "experienced" guys input as well. I also would be interested in some good info on parts.  It doesn't seem like the local parts places are much help.  I would like to replace the cooling system hoses since some of them are soft and swell when hot.  I am really impressed with the car.  It's a sedan that runs very similar to my old 944 Turbo.  I gave it up when the kids outgrew the back "seat".  Sure wish I had tried one of the XJRs back then as a replacement.  Thanks again.

for "experienced" guys input, there is no better place than right here in this very forum -- for jag parts, I've had success with the following:
1. motorcars LTD -- probably the best one - might need to contact them directly over the scroll-down, online shopping method.
2. autoparts world -- a cheesy name, but they're great (this is not the same as autoparts warehouse, whom I don't recommend for jag parts)
3. coventry west

My 98 XJR is also anthracite. welcome to the forum and enjoy your fantastic new ride!