Newbie - Te449

Newbie here with a new-to-me 2013 TE449, my first bike in a long time. Last fall I did a MotoVermont (https://www.motovermont.com/) week long dual sport ride for a friend's bachelor party and got the itch to get another bike. I found the TE449 locally with ultra-low miles (~1200), for a solid price and jumped on it.
It looks to be virtually brand new with some goodies added by a previous owner - Zipty oil recirculation, billet oil filter and fuel caps, radiator guards, breakaway levers, and Race Map II jumper.
Suspension wise it appears to have had some tweaks as well, someone swapped the rear spring out for an up-rated Eibach unit, 892.0060.0 which is a 6.0kg/mm spring. I ran a spring rate calculation on RaceTech's website and they recommend a 5.93kg rear spring based on my weight and skill level etc. so this Eibach unit should work for now, just need to reset sag.
On the front it appears my forks have been lowered from just looking at pictures of other bikes and seeing where my forks sit. What would be the best measurement to confirm whether or not the forks have been lowered? I see a lot of mention of lowering spacers but really have no idea where those would be internally. I'm 6 feet tall, ~240lbs so I could handle a taller seat height but for now as I'm getting used to the bike I don't mind it riding a little lower. Assuming it has been lowered, is changing spacers and/or springs a reasonable DIY task?
Thanks for any advice!