OK, it ain't tubes or Dynaco - it's a s/s Hafler DH-101 preamplifier

Just acquired a Hafler DH-101 preamplifier - functional and very clean cosmetically. (I built one decades ago and still have fond memories of it.)
I'd like to a full restoration of this new baby. I have a PC-4 cap upgrade kit that's a few years old but never installed/used. I assume the unused caps are still good, but perhaps not?
I've seen a variety of options, all the way from turning it into a tube preamp using 6922s:
http://www.musicaldesign.com/paspro1a.html
which seems like maybe overkill,
to Musical Designs' http://www.musicaldesign.com/MC_Haf_premod.html
down to the PC-4 kit.
Have also ordered a set of gold-plated RCA input jacks to replace those crappy aluminum ones
The PC-4 kit doesn't contain anything for the power supply, but assume newer and beefier caps wouldn't hurt.
Any suggestions would be much appreciated.
This will be driving a Hafler XL-280 amp in my "auxiliary" system.
Tnx
dave

a) A few years on caps is fine, and modern small-value (non-electrolytic) caps will last indefinitely.
b) New jacks are good.
c) P/S caps - upping the voltage by perhaps 25 - 50% is good. Upping the capacitance by the same is good. If you go any higher in capacitance than 50%, be sure to bridge them with a small 0.10 uF film cap. Not a bad idea anyway. And do check B+ to make sure it has not climbed too high. Try not to go over 50% in voltage - *some* (but not all) electrolytic caps get 'lazy' when under-driven by too much. It very much depends on the internal chemistry. This tends to occur at higher voltages in any case. My rule-of-thumb is nothing less than 35V in my stuff - even if only a 10V cap initially. And, if you can, look for 105C electrolytics. Heat is the enemy of electronics.

As to the rest of it - let it be for 50 hours or so before committing any modifications. These are surprisingly mellifluous preamps with a surprisingly good phono stage. You might be sufficiently content to let it be. And it is an excellent match to the 280.