It's pretty straight forward. As noted above it can test your patience because the pump lever holds the housing out a bit. You can use Glen's trick with the thread or simply put a bit of gasket shellac on the pump side of the gasket to hold it in place. I get one bolt started so the pump doesn't flop around while I start the other. I run the first bolt in just far enough to compress the pump lever a bit to make aligning & starting the second bolt easier. You'll get it. It isn't that difficult, about a 2 on the 1-10 scale.

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