all good ideas.... I need to 'get into this model' a bit, and see how i can remove some wood below the rails. The rails are mounted and under them is a large block of balsa that makes up the engine compartment and bottom part of the cowl etc.

So, i think first i need to excavate some balsa out below the rails so i can get o the blind nuts to remove them...then i think i can figure the rest out....with the methods suggested above.....

Thanks,
Chris