If your tub rims are modern and wide, then build up a good glue coat on them, hit the tub with some glue, mount and you should be OK, even at low pressures.
If they are narrow, then I've used a mix of tape and glue - but if you go down this route the removal process is pretty much destructive.
Anybody have any advice specific to glueing CX tubs on to carbon rims?
Need to do a fairly pricey set and despite having glued road and track tubs in the past I'm a little nervous.