20 in the wellhead 12 further a bop 22 is illustrated atop the conversion configuration 14 in this figure the bop blowout preventer is run and connected atop the wellhead adapter via another connector 13 such as an h4 connector in a single run the bop 22 casing 18 and casing hanger 20 are run during the drilling operation which as one of skill in the art knows will naturally have to occur during the sequence of preparing the borehole for its intended end use referring to fig3 and in another run tubing 24 and tubing hanger 26 are illustrated while being conveyed into the wellhead adapter 14 and the wellhead 12 further a spacer 28 is positioned at the tubing hanger to space the tubing hanger 26 from the casing hanger 20 previously installed by a selected distance in fig4 all components are illustrated in a landed position in another embodiment referring to fig5 8 and wherein like elements carry the same numerals as above and similar elements to those above are referred to with one hundred series numerals of the numerals used above the wellhead adapter 114 is provided additionally with a profile 130 therein that is configured to be engaged by a landing shoulder 132 run in subsequently with the tubing hanger 126 the profile 130 extends generally radially outwardly from a wall 131 of the wellhead adapter that defines the inside dimension of the wellhead adapter the landing shoulder 132 may comprise a snap ring collet or other expanding configuration with the capability of expanding into profile 130 in wellhead adapter 114 to lock the landing shoulder 132 in place the profile 130 may comprise any selected shape from a simple snap ring groove to a complex profile configuration and anything in.