Originally Posted by corndog67
Thanks guys, will try everything. The tanks been off for about 3 weeks.
If you can warm the tank up by placing it in a bath
of warm water for 30 minutes or so, the plastic will become more
compliant. Obviously you want to make sure gas doesn't exit the
tank and water does not enter the tank. As long as you don't submerge
the vent and keep the petcocks closed you should be fine. The idea
is to warm the plastic and thus make it more "willing" to be persuaded
to the shape which is required for fitting onto the bike.
The quicker you can try to mount the tank after the tank is removed
from the warm water, the better.