D4 main clutch stuck

Hi Kyle--my 7U manual shows that it can be removed thru the top cover---i would try backing off the clutch adjustment collar and then really put a lot of strain on the drive train to put a lot of torque on those clutch discs

You may get lucky and be able to free it but the problem is usually that the fibre clutch material has rusted and welded itself to the flywheel and often to the pressure plate which can be hard to separate without splitting the tractor.

I had one that refused to move even when the tractor was 'split' and a front-end loader was used to bounce the transmission area to break it apart. It was being used for parts anyway but we were amazed at the force needed to separate the clutch plate from the pressure plate and flywheel My D2 was similar and the clutch disk had to be destroyed and chipped out of the flywheel teeth to free it all up.

Hopefully you will have better luck and it may pay to fill the bellhousing with diesel first to try to free it - leave it to soak for a couple of weeks and replace the clutch disc afterwards.