Freeing stuck FR/FF from NGF-S focuser

Hello:

I have been using a JMI NGF-S Focuser in conjunction the a Meade F/6.3 Focal reducer/Field flattener. The setup has worked well. Now I wish to unscrew the FR/FF from the focuser. I am having a hard time as they now seem to be welded together(figuritively speaking). No amount of reasonable pressure or change in temperatue has worked. Any suggestions?

Thanks in advance!

Tom