Hi
The solution for difference in location of water pump on later 235 and 261s is an adapter plate.
more on the adapter plate see
http://canadianmilitarypattern.com/2...ifications.htm cost of the plate is small compared to the time to make one. Here is the guy I purchased my two plates from
pre68bowtie@hotmail.com .
The time consuming part is finding the correct water pump with the short shaft and the correct size pulley. Short shaft is necessary for clearance to the radiator and the correct pulley size is to keep the fan speeds reasonable, should be the same as the engine RPM.
Hope this helps.
Cheers Phil