Originally Posted by
T-Mar
As previously stated, thread difference is not an issue and loose or 3/16" earings can be used. If the Tange is ISO standard, the cup and crown race diameters should also be compatible.
The one problem area may be stack height. The Record Strada has a stack height of 39mm while Tange headsets can be much lower, 33mm on the Levin for instance. If the steerer has been cut to the correct length for for the Tange, without using spacers, then there my no little or no thead for the locknut to engage. The rule of thumb is that the locknut should engage at least three full turns.
My experience with Levins is that older ones, like from old Treks, are the same stack as the Record Strada, while modern ones are lower in stack height.
To the OP: You can measure the necessary stack height by subtractng the length of head tube from the length of the steer tube, with all headset parts removed.
In addition, the cups in these headsets are pressed into the frame and onto the fork. Correct pressing is necessary to ensure correct race positioning. If you can't adjust it properly at the end of the job, you might need to start over and have the frame and fork crown machined (reaming and facing) to ensure proper mounting surfaces. Good bike shops can do this pretty cheap.