WC transmission change

Hi!
I've just found out that I have a gigantic crack in my WC's transmission housing. Water must have gotten in there an froze n broke the casting.
I have looked at the service manual and it gives a vague description on how to pull it apart, and looks pretty straight forward. But I do not want to wreck anything as I go about this.
Can some one give me a little advice as how to go about this?
What is the most time efficient method of changing a transmission in my '39 WC?
I appreciate your help!
thanks bushnellman

Couple of different ways...if you have adequate blocking/support for the front half, you can unbolt the rear axle and pull it away, then replace the transmission. Lacking that, leave all wheels in place and pull the engine and clutch housing, then replace the transmission from the front.

The transmission pulls forward away from the traction release lever housing...the casting immediately to the rear of the transmission. There is a formed steel collar there, with a cork seal in it. Pretty sure the seal is not available, but if you go to a well driller, sometimes a good hardware store, you can get an impregnated cord/rope that can be used to make a new seal. Some kind of packing cord, forget the name now. Maybe pump packing?

Hi
I was cleaning the tractor up to do a little painting after an engine rebuild and found this crack, so my best route seems to be to pull it out the front, but to get the new tranny from my spare parts tractor I'll need to probably pull the tractor apart, so it looks like I'll get the opportunity to do both ways! I'm a lucky guy!
when I pull apart the parts tractor I'll want to reassemble it, so my question is: as soon as I remove the bolts holding the frame onto the back axle the back end will naturally fall to the ground, right? I'm gonna do this out in a field where I have nothing to hold it up unless I block it up also( sounds as if I just answered my own question) but there doesn't seem as if there is any flat surface left to block the back end up...I'm trying to think through the process of reassembling the back axle to the tractor,( this "parts" tractor I am using as an lawn/field ornament so I want it to "look" like a complete tractor)It would seem to be a lot of work to try and pick up the rear end if it were to fall to the ground!
My parts tractor and my shop are about 300 miles apart, I'm making a trip up there tomorrow to collect some other parts and ill be able to take a good look at the whole situation, and thanks for your input! I will be able to formulate a plan of attack
thanks again, bushnellman

If your ability to block up the parts tractor is limited, why not do both from the front? A handy tree and a winch can hold the engine up...the rest is small stuff. BTW- take one side rail loose or off and things will move easier, yet it still holds the tractor up. Use a splitting wedge at the front steering casting to spread the side rail.

if you'll build up your cribbing under the rails, then take out the four rear rail bolts and then the rear just rolls out of the way
<a href="http://s33.photobucket.com/user/Joecdeere/media/1941%20WC/wcpics%207_zpslijxkm5g.jpg.html" target="_blank"> </a>

Just a suggestion, if you unbolt the rearend from the frame rails, be sure to chock a wheel and lock the brake, if it gets away from you and flips over you will have bent brake levers. Don't ask me how I know, lol.

A few years ago I bought one of those PTO/belt pulley seals, don't remember where though.

Well... got it all tore apart had a little trouble following simple instructions LOL! but after loosing up the front end and spreading it out it worked great!
I went to my parts tractor and found out I had a different transmission, I haven't taken time to ID it but its seems to be original, and it is also the same year WC.
whats the best advice on trying to seal up crack in old one?
JB weld? I've got a relative that's a really good welder, but alas he owes me money and will not answer the phone...go figure eh!