I have a custom module that has two models, simplified:

class bom_checker_how_many(models.Model):
     _name = 'mrp.bom.howmany'
    bom_line_stat_ids = fields.One2many('mrp.bom.howmany.bom_line_stat','bom_checker_id') 

class bomLineStat(models.Model):
     _name = 'mrp.bom.howmany.bom_line_stat'
    bom_checker_id = fields.Many2one('mrp.bom.howmany')

The module works good, but when I want to uninstall it I get an error message that it can't delete the model due to it's dependency to the other model. So when I hit "Uninstall", the module is only partly removed.

Now, the models are left behind in the database, so when I try to install the module, I get another error saying that it can't install because that the models are already existing.

1. Should I declare my models any different to be able to uninstall/install properly?

2. Can I in an easy way manually remove the models from the database? I can't do it through the GUI, it says "Model 'mrp.bom.howmany' contains module data and cannot be removed!"