Posted by dave horvath on Wednesday, September 25, 2002 at 10:25AM :
The first PW transmission was the NP C-38126 crash box spur gear type 1945-49. Easy to remember because 126" is our wheelbase. It takes the first bellhousing.
The socond transmission was the NP C-38711 crash box 1950-54. It can be used with the first or second bellhousing. Easy to remember because of the convenience store.
The final transmission is the NP 420 synchromesh 1955-68 (and export M601s through 1978). It takes the third bellhousing. I believe it can be used with early bellhousingwith 1/4" spacer.
Source: Article in Power Wagon Advertiser by Mike Flieg of VPWs. Hope this helps.
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