i've just finished a viscount conversion
had same issue with threadless bb
i just replaced the pushfit bearings which are standard off the shelf numbers
ordered online from a bearing merchant
reused the original spindle
whacked on a sugino chainset and jobs a goodun
today bagged a carlton corsair 531 frame n fork for a tennor from jumble at mcr velodrome.....which gets project no2 into the workshop
cant get enough of this fixed lark
Got any photos? I have a Viscount conversion myself but my BB has been threaded at some point and a cup and cone BB fitted. i had issues with a modern replacement as the down tube comes a long way into the BB shell.