Stuck jd 520 clutch assembly

I was wondering if you have any ideas or trade secrets for taking off a stuck clutch plate assembly for a JD 520 circa 1958. It has a hand activated clutch. The disks and plates are located inside the belt pulley assembly. The initial clutch disk comes out fine. The stuck part is the large assembly just after the first (or outermost clutch disk). It is mounted on a splined shaft and has two tapped holes for use with 7/16 bolts and a gear puller. I tried the bolt on gear puller illustrated in the repair manuals and it refuses to budge. I put enough pressure on the tapped bolt holes to partially strip the threads out of one so it had to be tapped deeper. then I tried a small 3 arm gear puller, liquid wrench, and a bit of heat and light tapping with a small hammer hoping it would loosen it. I have been applying more spray on penetrating oil (liquid wrench like stuff) daily and will try the bolt on puller again if noone has any other suggestions.
I like this tractor alot and prefer to do this work myself. Every time I bring it to the john deere shop nearby, they use it as a training tractor for their new help and it comes back in worse condition than it left.
I still need to rebuid the power steering pump from the local john deere shops last 3 attempts to fix it.

So...any advice, suggestions, and help about power steering pump rebuilding and how to remove this clutch assembly to replace the inside disk from the tractor restoration experts like you would be greatly appreciated. Thank you for your time and i look forward to hearing from you.

Sincerely,
russ lante [email protected]