[modeller_usage] loop positioning

Hi All, A quick question. I have a pair of beta strands in a GPCR. Experimental evidence suggests that the distal portion (2nd beta strand of the loop lies underneath the proximal part of the loop (1st beta strand). I have used modeller to model this region , but all of the models have the distal part ontop of the proximal part :-(. Does anyone know how I can restrain the orinetation of the loop fragments so that the start of the loop is ontop of the end on the loop. Thanks again John