Springs in Sanwa stick

I have a sanwa jlf stick and I’d like to tighten the springs to get a bit better response out of it ( and help my shitty execution lol). What size replacement springs will fit inside this stick?

Additional Spring:
Sanwa JLF
Seimitsu LS-32(-01)
Seimitsu LS-33
Seimitsu LS-55(-01)

Home Depot Spring.
http://www.shoryuken.com/showthread.php?p=6593187
http://www.shoryuken.com/showthread.php?t=222408

which would you recommend and how easy are they to install?

Install.
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