Deere 2355 hydralic pump repair

[varmint]

A friend is rebuilding a 2355 that had a barn beam drop across it, and he's about done, except the hydralic pump needs a new seal on its shaft, and he found out that his pump, the larger of two available on that model tractor, (2.4 cubic inch?) has to have the pump disassembled to remove the shaft before resealing. It looks complicated as ****, and before we tackle it, maybe somebody who knows about such things could give me some advice? We'll post a picture of the restored tractor when it's done- the paint work is beautiful. Thanks.