Kt66 or el34?

[Benjammin]

Hey everyone. I recently bought an already assembled jtm45 kit from ebay for around 1 grand. It has a mars tran transformer, sozo caps and everything else from this kit http://valvestorm.com/JTM45%20Kit thats supposedly made up of the parts that metropoulus amps use. Ive been pretty happy with it so far, but im having trouble deciding whether i should keep the gold lion kt66s or putting some svetlana el34s in it. The tone im really after is this http://www.youtube.com/watch?v=jy3tVkp2Jdc . With the kt66s it's nowhere near as agressive sounding or "barky" as the jtm50 in the video. Since the jtm50 uses el34s, i was wondering if id be better off swapping to them instead of using the kt66s. Id like to also add that i care nothing about clean sounds, just a good crunch. Im running the amp through a 1960tv cab with greenbacks along with a gibson les paul standard with wizz PAFs and a gibson angus young signature sg if that helps. Any advice is appreciated, thanks!