Height? or Length...
Hi Terry, the ASK21 is a 'Sit up and Beg' type of two seater where you could add additional Confor safety foam seating to improve your visibility. The pedals should adjust Ok. You might also be able to find a thicker parachute, to push you forward a bit.
However some of the more aerodynamic single seaters, have you laying more horizontally, so height now becomes length... as you lay on top of your parachute.
My unique problem is that I have short legs and a long trunk, so fitting in a wooden K8 needs the pedals all the way back, and then whilst lowering the canopy, it hits my head if I don't duck.