'36-39 left case race conversion to '40-up, need help

Not real sure I understand the question...???

Your year model has the pre-1940 "blind bushing" and your wanting to use the 1940-1948 "open bushing....

The blind bushing has a plate across its outside opening which the OEM case race bottoms on when pressed in. This plate has three holes in it for pressing the race out for replacement...Because the plate blocks most of the outside opening, line lapping is not possible....

And for this reason you want to install the later 40 and up....

Am I on the same page here with you so far...???

100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3

There is no "KIT" for conversion. It is a very simple and straightforward modification. The ID of the cast in portion is the same for early and late cases, the difference being the closed end on the early ones. The closed end needs to be cut out of the case, by milling it, lathe boring it, or even cutting it out with a die grinder! The case race surface is not affected by removing it. Then a standard '40 up race is pressed in and line bored. The lip seal is a totally different aftermarket item, but the race needs to be upgraded first. No late race, no lip seal!
Robbie

^^^ There it is ^^^
HD part # for the 40-up is 24595-40
.005 oversize...................24597-40
.010............is after-market....
=============================================

If you wanted to overkill that....
Could bore out the case for a 69-up Timken and run a 81-up spline keyed motor sprocket shaft.....

That is if you was thinking of running "Boost"...

100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3

This was not really a WTB ad, i'm not looking for old parts, i was looking for help and direction on where to get them...
That and i was trying to understand the procedure..........

But thank you Robbie and Dragstews, i think that is what i needed to know. I was trying to wrap my head around it to understand it better.