Sorry if this has already been covered recently but I've just upgraded my droopy front end with racetech emulators and 90 springs.
Firstly my damper rod had 4 holes already at the correct size so only 2 more to drill each side. Then unfortunately the oil lock piece jammed in the fork so I had to fully dismantle one side

To replace the new fork seal I bought a length of gutter downpipe from Wickes which was a perfect fit. Also Lissa cut some pieces to use as height measures for dropping the forks through the yokes. Presently at 5mm to the top of the tubes, not caps. Lastly I purchased a short length of small bore tube and pushed it through a bit of of ply. Using cable ties and tubing I have now got an air gap tool that using a syringe, or in my case Mityvac, draws the oil out so you have equal and accurate air gap in each fork leg.
Also while the forks were out I regreased the steering head bearings and rather than use a punch on the stem nut I bought a tool from my local pushbike shop for 7quid.
Pics below.
Incidentally with the 90 springs,emulator on 3 turns, 20mm of preload, and 130 airgap with 20 wt oil it still feels a bit soft.