Help: simulated OS/8 gen

Dear all, I'm trying to construct an OS/8 environment under SIMH. I'm trying to use an RK05 device for the SYS volume, but can't seem to get the BUILD procedure right. The OS/8 distribution I grabbed is dectape images of V3D from http://www.pdp8.net/images/images/misc_dectapes.shtml. Here's what I've done so far: sim> at dt0 Dectapes/AL-4711C-BA.tu56 DT0: 12b format, buffering file in memory sim> at dt1 Dectapes/AL-4712C-BA.tu56 DT1: 12b format, buffering file in memory sim> at rk0 sys.dsk sim> at rk1 user.dsk sim> b dt0 .R BUILD $ At this point, I can't seem to INSERT or SYS anything resembling an RK05 system disk. If I: $LOAD DTA1:RK08SY then I can: $SYS RK8:RKA0 but when I try to do BOOTSTRAP I get: $BO ?SYS $ I also fiddled with PIP and the /Y and /S flags, trying to just build a copy of the tape on the disk, to no avail. I'm sure I'm just a dunderhead. Can anyone provide some hints? Thanks, De