Trenmec TKO info

I have a 69 428 CJ with 4:3 Drag pack rear end gears and will have around 550-600 HP at the fly wheel. THe reason for this type of choice is to have the best of both worlds on the sreet, with both bottom and top end durability
I am thinking of installing a TKO 6 speed Trenmec, will it fit or will i have to modify the tunnel?
Will the TKO model handle this type of HP?.
Is there any other choice for me on the maket?
What would be a suitable clutch to suit?
It's a lot of ??? but I learn a lot from this site and knowledge of the people hear is the best.
Chris from OZ
PS Hope the spelling is correct im drinking JD and having a good time.